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-   -   climbing issues (http://www.buggymasters.com/forum/showthread.php?t=4174)

MASTERBATES 04-11-2013 09:33 AM

climbing issues
 
so there are still 2 hills that i know of that i cant make it up. i can get almost all the way to the top.then i dont have enough power to keep pulling. this can be agrevating. i can always winch my way the rest of the way up,but dont feel in myself i should really have to from all of the mods ive done so far. so far all my gearing is stock, i have a 14-39 tooth sprocket setup,and i'm unsure about the internal gearing. im curious if maybe stepping the front sprocket up a couple teeth would help? the only thing with that is would it relieve stress on the transmission or not? i have added weight to the buggy by adding a body, could anyone lend me some input? muchly appeiciated

SLESTAK75 04-11-2013 10:42 AM

That 14-39 gearing sounds pretty danged aggressive to me. Unless like you said the internals are high. One thing I can see ( not sure how much this will affect it ) But with the 2000rpm clutch springs the clutch wont hold on as long, as your speed and rpm's diminish on the hill. The taller rear tires also "raise" the gear ratio. If you have the stock wheels/tires, switching back to those might give you all that you need. If you make the 39t larger or the 14t smaller you will get more pull at the cost of top end speed, or you could see what your internals are and change them accordingly. The other alternative is to go big bore.

SLESTAK75 04-11-2013 10:53 AM

Also, the A9 cam is not designed for power in the lower rmps. The A12 would be a better choice if your desire is to climb hills.

mb1134 04-11-2013 11:45 AM

I was thinking the same thing about his cam. I am thinking of possibly switching to the A12 myself now that i have everything else. I love me some bottom end!

SLESTAK75 04-11-2013 12:52 PM

I love the A12 in mine. It gave me more top end as well (compared to stock) but the biggest gain is lower to mid RPM. I'm sure the opposite is true for the A9. I'm sure it gives you more bottom end than stock but your greatest gains are in the top end. In my opinion I think the A12 and buggies were made for each other. Because its heavy it really needs the power down low for takeoff and acceleration. I'm sure there are those who disagree though. That's just my take on it.

Miamieddie 04-11-2013 01:00 PM

11gram sliders may get you up there and you'll keep your top end. Just my oppinion.

MASTERBATES 04-11-2013 11:14 PM

Thanks for the input guys. It means a lot.I really need to stick with my taller tires, due to ground clearance on the trails. I suppose I could give the A12 can a shot, but with that should I also consider the stiffer springs to compliment it from floating the valves? I cruise gravel roads and any top end speed i could keep would be a big help.,ugh it won't be long now till the BUGGY BASH in Missouri, and I got another project on my hands regarding my honda350R,it would be nice to take it but the way income is I doubt I'll have it ready. I have been debating on possibly trading it to someone with the $$$$ and time to complete the project,in exchange for another gy6 buggy that already is trail ready for the wife to take. In my region on Craigslist these gy6 buggies come few and far between, and people who want to get rid of them seem to always want to trade up for cars, and trucks. Seems a lil outta spec to me regarding a trade, lol. Anyways where would be a good place to find a different front sprocket? It seems like I have looked before with no such luck.

MASTERBATES 04-11-2013 11:20 PM

And also regarding cam sizes, what are the benifits such as say the lobes from a stock came, leading up the the A12 and beyond, I have even seen an A15 cam! I was like holy crap, I'll bet that would be "bent valve hell" lol

SLESTAK75 04-12-2013 06:41 AM

The A12 doesnt have the lift that your A9 has so it will be easier on you springs at high speed. The A12 has a longer duration which is where the low end power comes from. I think youll be happy with the A12 and you wont loose much top speed. The cam could quite possibly be all you need. But on the sprocket I am unsure.

MASTERBATES 04-12-2013 09:36 PM

Well judging from my mods already,I stepped up 1 more from an A12 to A13 can should be in by Monday hopefully

Johnny 5 04-13-2013 09:18 PM

When we go up steep hills I have found that if you can slow down and let the cvt down shift a bit and hold a lower rpm and when you are almost to the top open up the throttle.

If you hit the hill at max speed you cvt is in higher ratio and will bog down. Try to go half throttle and lower rpms. This works for me when we climb steep hills I come to almost a stop and go slow and steady and make it almost every time.

Johnny 5 04-13-2013 09:26 PM

I noticed you are running a 140 main jet. What size was the stock jet? Also does your fuel have ethanol in it? Our fuel I think is 10% ethanol. I have a 125 main in the blue buggy and it is pretty close, might go up to a 127.5 that I have. My 155cc red buggy with a 122 main and 34 pilot runs fast and climbs well.

MASTERBATES 04-13-2013 11:39 PM

My stock jet was originally a 111 with a 35 pilot. After my first simple mods it required a 132 to tan the plug, after port& polishing my head, which o took quite a bit out, it tans at 140. I have also tried what ur talking about johnny with the cvt,down shifting first, it just doesn't quite make it tho. I've added a lot of weight with the sheet metal body and winch, plus me I weigh in @ 210, add another 210 for a passenger my same size, and I'm already over the buggy weight limit.

Johnny 5 04-13-2013 11:52 PM

Maybe you need a 5hp shot of nitrous.

Johnny 5 04-14-2013 12:08 AM

It would be nice if there was a way to hold the cvt in mid shift so the motor could rev to max rpm. Like a low and high range.

Do you have a stroker crank? My wife's blue buggy with the 3mm stroker has good climbing torque it just dosnt rev like the 155cc stock stroke motor.

ckau 04-14-2013 06:13 AM

[QUOTE=Johnny 5;32427]It would be nice if there was a way to hold the cvt in mid shift so the motor could rev to max rpm. Like a low and high range. QUOTE]

Try the 2500lb (red) contra spring. this will prolong the upshift slighty but more importantly allow downshifts at a faster rate. When you aproach a climb back off the gas a touch to allow a down shift to occur then power up. With the right timing you can approach a climb at speed then get that lower ratio needed to get over the top. Back off the gas too soon you'll be back in top gear before you finish the climb. too late you'll loose momentum and traction.

MASTERBATES 04-14-2013 10:22 AM

My contra spring is red, but the box says its a 2000,ckau, u know where I could find a 2500? I don't recall seeing any before

SLESTAK75 04-14-2013 11:46 AM

I think you'll do much better once you swap that cam out. Im not sure the specs on the A13 cam but if it adds even more to the bottom than the A12 you should be able to pull without changing anything in the CVT. if you have the red spring you already have the best downshift you can get. You just need that little extra power. The timing tips are also very good advice.

ckau 04-14-2013 05:23 PM

Quote:

Originally Posted by MASTERBATES (Post 32439)
My contra spring is red, but the box says its a 2000,ckau, u know where I could find a 2500? I don't recall seeing any before

my bad, your right I wasn't paying attention.

MASTERBATES 04-15-2013 12:58 AM

fortunately my timing marks for the flywheel and TDC are acurate i made sure when i had my head pulled for the P&P. johnny id like to invest in a stroker,but im not really wanting to pull and split the cases until the day the enginelays its egg,lol...and when that happens, i have an 87 quadrunner with the long engine and cvshaft independent rear end, i only have to dip into the bottom end of it to figure out why it wont stay in any gear. it will slightly build a rev and then jump and grind.....ugh im dreading that bottom end too cuz its so aqward and long. but if i get it lined out, those rhinos better move over down that gravel road,haha

MASTERBATES 04-20-2013 11:43 PM

Got my A13 cam in the other day,installed it and WOW what a difference it made, it pulls through all the ranges and can't even feel the transition from low to high range, a friend and. Went out metal detecting today with the buggy we were past the 400 pound limit and it took all we dished at it on the trails. This is by far the best I could ask for out of a beefed up gy6 engine. I'm keeping it just like this for as long as it holds up:banana:

Johnny 5 04-21-2013 01:38 AM

That is cool that you got such positive results, Hope to hear more about the A13 cam.
I put A12 in both our buggys and like the power for our ridding style.

SLESTAK75 04-21-2013 05:31 AM

Awesome Master. Glad to hear you like the results. Its amazing what these little 150's can actually pull if set up right.

xlint89 04-21-2013 08:23 AM

Glad to hear you got Xactly what you're looking for with your set up now.

The A9 cam really is meant more for the light weight scooters. Not saying it can't be used on a big engine GY6, just not practical for most of us.

It does appear the A12 or 13 in your case is really a good choice for these heavier buggies. I did like the performance I gained from my A11 but think they have some tight tolerances you need to pay attention to. (exhaust valve to piston contact to be specific) I am presently using the A10 right now and find that it has great mid to upper RPM power. I am currently trying to see if I can adjust my carb for better bottom to mid performance.

As it sits right now, it takes off really hard, then kind of falls flat a bit, then really wakes up once the RPM starts to get in the higher range. So if I can't "tune" the flat spot out, I will most likely be going back to the A11 or trying an A12 and see what happens.


Currently my set up is a NCY 2.2mm stroker crank, NCY 58.5mm Nikasil cyl, NCY 58.5mm ported head, NCY SS valves, Taida valve springs, Ported aluminum intake manifold, Mikuni TM 28mm flat slide carb, NCY CDI, Bando coil, iridium spark plug, and a TK exhaust.

CVT set up is all stock except for the Scooter Ninja 14g sliders. Stock Yerfdog internal gearing (13/40 I believe) 16T drive sprocket, 36T axle sprocket, and 22" rear tires.

SLESTAK75 04-21-2013 02:43 PM

Quote:

Originally Posted by Johnny 5 (Post 32678)
That is cool that you got such positive results, Hope to hear more about the A13 cam.
I put A12 in both our buggys and like the power for our ridding style.

I agree with johnny. I hope you will give a more detailed impression of the A13 cam. You have me curious as to whether the A13 will make more power than the A12. I wish there were someplace to get details on the specs of these things.

Johnny 5 04-21-2013 03:21 PM

Hey slestak didn't you say you met Mr A12? Maybe he might know Mr A13?
I think that the A12 or A13 cams are a big improvement over stock with the more lift and duration.
My Wife's big bore stroker motor 183cc with the stock cam was a dog above mid rpm. The 155cc with a stock cam would beat it every time heads up drag race after about 75 feet and would pull away. The 183cc with the stock cam would climb like no other just no top end.
The A12 is for low end but I got power all over the rpm range up to 8600rpm when it maxed out at 33mph with the 39t sprocket. Probably the carb or exhaust kept it from going higher witch is a good thing. I am now going to keep the rpms below 8000 because with the 31t and the 13/43 gearing I would hope to get a max speed of 35 to 38mph and a cruise speed of 30mph. Any faster on the trails and it could be trouble.

SLESTAK75 04-21-2013 03:52 PM

Your right Johnny. I have the A12 in mine but if an A13 or even the A14 would make even more power than the 12 it sounds good to me.

http://totalruckus.com/phpBB3/viewto...?f=116&t=54341

Check that out.

MASTERBATES 04-21-2013 05:48 PM

:dunno:I wish I could get more detailed for you guys, all I can really say is if your looking for down low tourqe that will pull from bottom to mid onto the top end. Give the A13 a shot, u might not want to step down

SLESTAK75 04-21-2013 05:56 PM

http://www.scooterchinois.fr/uploads...5d6ea6858f.jpg

Here's another. Only problem is it doesn't have the A13 on it but you can compare the a13 & 14 on the previous post.

SLESTAK75 04-21-2013 06:00 PM

Unless Im misreading those specs ( which is quite possible ) It seems that the A13 would be similar to the 12 on bottom end and maybe even a bit more , but it seems like it will give more on the top end too.

Johnny 5 04-21-2013 07:28 PM

So master have you tried to go up those two hills yet? That would be a very good test to see if it really made the difference.

MASTERBATES 04-21-2013 08:23 PM

I have been up one with a friend on board, before,it would stop about 6 ft, from its peak, now it will slow down at the 6 ft. Mark and the true engine pulling begins, it lopes it the rest of the way to the top, with me riding alone, it will pull up it effortlessly,

MASTERBATES 04-21-2013 08:27 PM

The other hill I have yet to go up,will require taking a sledge hammer and busting up a good sized rock, the rock has a flat edge on it as tall as my front tires.I always had to winch over it, but its a sandstone bedrock mix.. so a lil sweat should bust it down enough to not have a problem

SLESTAK75 04-21-2013 08:52 PM

The things we do for fun. That rocks that you pulled that hill like that. I pulled a long hill the other day with me and my dad in my already heavier than most buggy. We were nearly 400lbs cimbined and I was amazed at the pull these things can have.

Johnny 5 04-21-2013 11:18 PM

I didn't climb any hills today just climbed into my buggy to try out the 13/43 gears. Went easy for about 5 minuets to break in the gears and changed the oil with Lucas 80w/90wt. The oil drained out had the same glitter that I remember from kindergarten. I will change it two more times or until it is clean. For 9 bucks I can change the gear oil like ten times.

Just don't over tighten the drain plug like I did a year ago and strip the threads and have to use a thread insert to fix it. I recommend to replace the drain washer to prevent stripping the threads.

mb1134 04-22-2013 05:39 AM

Sounds like Masterbates has been having fun. I can tell you that i took mine out this weekend and i had absolutely no problem pulling up hills. This thing kicks *ss. It had mad torque up any and all hills. I only got stuck once, and that was due to trying to go over some big roots going back up one of the hills. I was extremely suprised at how well it ran. I never expected it to be able to run this great. I am extremely pleased with this setup.

MASTERBATES 04-22-2013 12:24 PM

How many CC are u pushing mb? Ya I been haven fun ALOT, with the added stress I think I might switch to a Kevlar belt

mb1134 04-22-2013 01:02 PM

I go the 62mm kit so its suppose to be 180cc

SLESTAK75 04-22-2013 02:33 PM

Quote:

Originally Posted by MASTERBATES (Post 32715)
How many CC are u pushing mb? Ya I been haven fun ALOT, with the added stress I think I might switch to a Kevlar belt

You won't get better grip from a kevlar belt. It is just designed to last longer. Thats great you may think but wait. Belts will wear on the pulleys and kevlar belts being tougher will wear out pulleys faster. Also if you have some sort of failure in the cvt or gears or anything like that. The belt provides a "weakpoint" that will break before anything else does. Having a kevlar belt removes a bit of this security as it will take more to break it which allows more time for something else to break. Gates powerlink belts have been recommended by many. The choice is yours just giving you some points to consider.

MASTERBATES 04-22-2013 02:40 PM

Good point slestak

Johnny 5 04-22-2013 08:15 PM

Well said slestak, I run the power link gates also. Had to put a good used belt in for this trip this weekend because when I removed the engine to fix the blown out gasket the belt that is only 10 months old was cracked and got cooked from the heat.
I also drilled 3 8mm holes around the center of the cvt cover were the center lower vent is to increase air flow.

I cant remember who it was that removed the plastic cover and added mesh and a screen to increase air flow around the rear clutch pulley, That will be my next mod on my extra cvt cover that has the howhit plastic cover. Both bugys have solid cvt covers that some air holes would help but if any mud or water got in it would be not good.

Johnny 5 04-22-2013 08:22 PM

I have a formula for cc's. For the blue buggy( 62mm x 62mm x 60.8 x 0.7854 = 183 cc's)
It is bore x bore x stroke x 0.7854. I will say the 183cc motor has a bit more vibration than the 155cc stock stroke motor. But the Beach Boys did sing about good vibrations.

SLESTAK75 04-23-2013 08:28 AM

Quote:

Originally Posted by Johnny 5 (Post 32731)
I have a formula for cc's. For the blue buggy( 62mm x 62mm x 60.8 x 0.7854 = 183 cc's)
It is bore x bore x stroke x 0.7854. I will say the 183cc motor has a bit more vibration than the 155cc stock stroke motor. But the Beach Boys did sing about good vibrations.

I thought about this vibration a while back. The flywheel is weighted to counterbalance the stock piston. Larger pistons weigh more and throw the crankshaft out of balance. I was wondering if you could re balance the flywheel somehow. Any thoughts??

Johnny 5 04-23-2013 09:45 AM

That is true but to find a place to balance might be tough. I am going to put a 3mm stroker in my red buggy this summer and keep the 58.5 piston to see if the small bore long stroke works better. The 183cc makes good low end but at top rpm it is a bit lazy from the extra piston weight drag and stroke. So the lower gearing 31/16t is better.

SLESTAK75 04-23-2013 03:58 PM

1 Attachment(s)
True. You would need to get to TDC and mark the flywheel in line with the piston and opposite the piston. You would need to know the weight difference in the two pistons and either subtract that weight from the piston side of the flywheel or add that weight to the side of the flywheel opposite the piston. It wouldn't be perfect but it would be better than the way it is. Just my thinking on the matter.

ckau 04-23-2013 06:55 PM

1 Attachment(s)
Quote:

Originally Posted by Johnny 5 (Post 32730)
I cant remember who it was that removed the plastic cover and added mesh and a screen to increase air flow around the rear clutch pulley, That will be my next mod on my extra cvt cover that has the howhit plastic cover. Both bugys have solid cvt covers that some air holes would help but if any mud or water got in it would be not good.

here it is

Johnny 5 04-23-2013 10:14 PM

Hey ckau with the cover mod can you feel the hot air coming out? I wonder if this will help also cool the motor because any heat removed will reduce heat from the engine.

ckau 04-24-2013 06:04 PM

Quote:

Originally Posted by Johnny 5 (Post 32781)
Hey ckau with the cover mod can you feel the hot air coming out? I wonder if this will help also cool the motor because any heat removed will reduce heat from the engine.

You can feel heat escaping through the opening. The cvt cover is noticeably cooler to the touch. The inside of that cover is like the interior of a oven. Anything you can do to allow heat to escape isn't a bad thing. The fan on the outer variator pulley is not that effective. It probably serve better as a heat sink to dissipate heat off the pulley more than it moves air. I'm using a computer fan and shroud to blow air across my oil cooler. I'm planning, at some point, to fashion something using the same type fan to pump fresh air into the cvt cover

toomanytoys2 05-08-2013 10:03 PM

Just a point about engine vibration. When an engine is designed, it has a probable RPM range that it is intended to run at. The engineers strive to have minimal vibration at this rpm range. However, we are going way outside of that range in RPMs. Also, when you also throw in a larger piston, it also throws the intended balance range out the window. On just about all engines, when you go a larger piston size, you get more vibration. What you can try is to weigh a stock piston, then weigh the BB then see if you can lighten up the BB with minimal grinding. If we were playing with twins, it would be easier to counterbalance. That being said, a germ of an idea can lead to some pretty good results.

Johnny 5 05-09-2013 12:04 AM

Lighten the piston what a great idea. I have a friend at work that tells me stock is the way it is supposed to be and any modification is robbing peter to pay paul. I disagree because the extra power I have been able to get from the gy6 is worth the mods and fun to do.

bear 05-09-2013 01:29 PM

It's always a balancing act, to make sure you dont go "over the top"!

baker3 05-09-2013 07:55 PM

Hey fellas, I dont mean to hijack this thread but im looking into buying a DR Pulley Variator, 11G sliders and red spring and wanted to ask about this A12 cam. If I buy one, how hard are they to install, will I have to rejet and where can I buy one? Also, are these upgrades gonna be a good investment?

xlint89 05-09-2013 09:42 PM

Welcome Baker.

11 gram sliders and the red spring will do well. The Dr. P variator will do very little in terms of improvement. The A12 will be a good investment as well.

Not hard to install. Yes you will need to rejet the carb after install.

But you will get best gains if you've done the other recommended stuff as in gutting the stock muffler or another exhaust, redneck intake, and also port matching the intake manifold and exhaust header will really reap the benefits of that cam. As well as a port and polished head.

SLESTAK75 05-10-2013 07:40 AM

These are very worthwhile upgrades. You will not be disappointed with them. The cam change will really open up the power. But as xlint pointed out, in order to get the full benefit it is necessary to open up the intake and exhaust. You will still get a nice gain if you don't match the intake but matching will give you the highest gain. Most definitely make a redneck intake as it is easy and inexpensive and needed. If you need help or have questions just ask.

baker3 05-10-2013 07:57 AM

So if I just buy 11G sliders can I just use them on my stock variator since the Dr. P won't make a big difference? I plan on making the intake this weekend but I really dont want to make the exhaust any louder than what it is now since my neighbors already hate me lol.

Johnny 5 05-10-2013 09:42 AM

I would start with the sliders and the spring in the rear pulley first and make changes one at a time if you can and keep a log book of results with the mods. I agree with the muffler due to noise, because louder isn't always faster. I only opened up my muffler tip by a 1/8 of a inch. Went from 5/8 tip to a 3/4 tip and it sounds a bit deeper. I first tried a 1 inch hole in my muffler and it was loud and ran poorly due to me not jetting it up.

SLESTAK75 05-10-2013 09:55 AM

Yes. The sliders will work just fine in a stock variator. Make sure to take the time to clean the ramps really well. I like to put some graphite powder in the ramp grooves too. A nice dry lubricant that doesn't cause problems.

xlint89 05-10-2013 08:02 PM

I'd like to echo what has already been said, yes the sliders will work in a stock variator.

If you want to experiment with a new variator, I hear the Kid n Me or the Motorio DR2 works quite well for about the same $$$ as the Dr P.

It uses 2 different ramps to boost bottom end as well as top speed. It includes weights with the kit, so if you want to go that route, you don't need to buy the sliders. OR you can buy it, and try the sliders with it as well. I think a member or 2 are using sliders in theirs?

It's a shame about your neighbors. The exhaust is pretty restrictive on some of these karts and can lead to a decent performance boost when opened up and the carb is rejetted.

baker3 05-10-2013 08:25 PM

I might say screw my neighbors and go ahead and gut the exhaust. I just ordered 11G sliders and the red spring so we will see how that does for me. Sorry to the OP for hijacking your thread.

SLESTAK75 05-11-2013 12:57 PM

http://www.scooterchinois.fr/uploads...527980b619.jpg

http://www.scooterchinois.fr/uploads...527b35b439.jpg

Here are 2 links that show the differences between all of the cams A8-A15. Good info. Remembering that more lift equals greater top end and more duration equals more bottom end, it really does look like for buggies that the A13 and A14 would be an even better choice than the A12. Durations are similar but with more lift and more overlap. The lift is still less than the really high lift cams like A9 but slightly more than the A12. It seems that those two would make more power all around than the A12. A bit more bottom and top end. Not quite sure what overlap does for a cam but I have read others say more is better. If you look close it seems that Master might be spot on with that A13. It has nearly identical lift to the A14 but more duration. It seems to have even more duration than the A12 plus more lift and overlap. Greater duration on the exhaust equals cooler engine "Johnny". I believe I will certainly be getting one of these A13's in the future. Any opinions??

xlint89 05-11-2013 02:39 PM

I know from the HD sight that cam overlap depends greatly on the exhaust system used.

A good exhaust can help pull a fresh charge of air/fuel into the combustion chamber during overlap.

Overlap is when both your intake and exhaust valves are open at the exact same time.

SLESTAK75 05-11-2013 02:42 PM

Awesome! Thanks xlint. So it seems that more overlap may or may not help, but it couldn't hurt to have it.

xlint89 05-11-2013 03:18 PM

This is not for our karts, but it does contain some really good info about camshafts and how to choose the proper one for your needs.

http://www.hammerperf.com/xlvalvetrain.shtml

Johnny 5 05-11-2013 08:25 PM

I am happy with the A12 and probably will look into a better exhaust. I don't think making the tail pipe bigger than 3/4 inch will help on the stock pipe. The inlet of the pipe is 3/4 inch on our buggies.

But I agree that the overlap is helped with the better flow of the muffler. I am thinking of getting some pre bent pipes about 7/8 inch and making my own header and using a dirt bike spark arrestor.

mb1134 05-13-2013 08:04 AM

I am intrigued by this A13 camshaft. I can't complain about A10 as of now, but i would like a little more get up and go on the trails. I think this is mainly due to the fact that my buddy i ride with has a RZR. I havent had any problems with hills or anything as of yet. Only problem i had was one hill. Saw some old boyin a brand new Jeep Rubicon with 3 inches of mud on his tires who didnt make it up. Then again he had street tires. I made it up really easy when i had a head start. But the second time was a different story as i didnt realize we were already at the hill. Its like a 2 section hill with about a 4 or so foot ledge before you hit the second hill. To top it off there is a good 7 or 8 inches of mud on the flat spot. Needless to say i gunned it at the bottom and once i hit the mud i slid all over and barely creeped up to the top spinning the whole way. I must say i am very impressed with the way this buggy runs. When it was stock i would have never imagined it running like this. The only complaint i have is that my buggy seems to run differently when i go up that 1000ft to the trails. I wouldnt think the jetting would need to be changed, but it runs so much slower and seems to be rich when i go up there. Normal elevation is about 800ft but 1800ft on the trails.

SLESTAK75 05-13-2013 09:13 AM

Its true MB. That extra 1000 ft can make that difference. Air gets thinner as you get higher so fuel mix gets more rich.

bear 05-13-2013 09:57 AM

Plus the steep incline will mess with the carb a bit!
@ Slezman, howd the interview go?!

SYCARMS 05-13-2013 11:09 AM

Quote:

Originally Posted by SLESTAK75 (Post 33231)
http://www.scooterchinois.fr/uploads...527980b619.jpg

http://www.scooterchinois.fr/uploads...527b35b439.jpg

Here are 2 links that show the differences between all of the cams A8-A15. Good info. Remembering that more lift equals greater top end and more duration equals more bottom end, it really does look like for buggies that the A13 and A14 would be an even better choice than the A12. Durations are similar but with more lift and more overlap. The lift is still less than the really high lift cams like A9 but slightly more than the A12. It seems that those two would make more power all around than the A12. A bit more bottom and top end. Not quite sure what overlap does for a cam but I have read others say more is better. If you look close it seems that Master might be spot on with that A13. It has nearly identical lift to the A14 but more duration. It seems to have even more duration than the A12 plus more lift and overlap. Greater duration on the exhaust equals cooler engine "Johnny". I believe I will certainly be getting one of these A13's in the future. Any opinions??

Just to chime in on camshafts. Cams are the most complicated part to figure in the engine. Most Chinese cams from my experience are inconsistant at best. I found this out when degreeing the different cams to post on my website years ago. You can have 3 A-12 cams from different suppliers and they will differ greatly. The numbers given on the cams mean very little for the purpose of tunning. The A-# indicate the use of that particular cam. A-12 is for low end torque has a higher lift but lower duration or valve overlap. The A-8 has a higher lift and more duration or overlap for more top end. The A-10 & 11 have the highest lift with moderate duration or overlap for all around performance.
Timing sequence with the opening and closing of the valves is what makes one cam different from another. A good example is buying a pulling cam for your truck. If one pays attention you will notice specs from each mfg. Crane, Isky, Lunati, RHS, or Ultradyne all claim for towing but their timing event specs differ. Well lets imagine if these mfg's all changed their specs to A-12 instead. This is what the chinese offer us. Some chinese cams will list numbers on their packaging like Int. 27.4mm Exh. 27.37mm, these numbers are worthless. Timing events are the only true way to tell a cam's performance capability. One must keep in mind that most sellers of the chinese perf. parts are selling to scooter owners, where as these cams have been designed for the much lighter scooter so the results they claim may not meet your expectations. Also as one posted above that with the A-13 cam he cannot get up the hill. First the 2000 tork spring is probably what is hurting you.
I have personally tried every cam available from A-15 to A-8 and have found the A-8 &9 to be very close in grind, A-10-A-11 as well. The A-12 stands alone which was the first perf cam available to the scooter/buggy world. Another important fact to remember is all cams are not created equal. For instance most Chinese cams first production will differ from others due to them not recalibrating their cutters. The Taiwonese do a much better job of this for they have more western values but this drives the price higher. Also the Chinese will sell their seconds (out of spec) cams cheaper. Eg. say I design a cam and contract with China to grind them. Upon completion of the run I inspect them to find they are not within my specs and I refuse the order, they will discount these cams to another vender so as not to have to start all over loosing money, then mfg. me my new batch. This is why it is difficult to list the specs on the chinese cams from one A-12 to another. Taiwon has a much better quality control for they check the specs prior to acceptance making sure the parts are within their tolarences. Now the Chinese have gotten schrewd since they consider Taiwon to be part of China some of these parts will be marked Taiwon but in reality they are not. So if you do find a good supplier of parts you stick with them.

SLESTAK75 05-13-2013 11:23 AM

Quote:

Originally Posted by bear (Post 33306)
Plus the steep incline will mess with the carb a bit!
@ Slezman, howd the interview go?!

No good. Wont be getting that job. At least my wife is working now so it isnt AS desperate of a situation.

SLESTAK75 05-13-2013 11:26 AM

Looking for work is a bit of a climbing issue right?? On a good note. I have started to pull in a bit of electronics repair and mod work. If that picks up I could do pretty nicely.

mb1134 05-13-2013 11:36 AM

Hey Tom, any word on the JCosta? Also, do you see any issues with running the A-12 or A-13 on your big valve head? Any issues with float on these bad boys?

SYCARMS 05-13-2013 12:15 PM

I'm hoping to see them this week. The A-12 will be no issue, I was never a fan of the A-13 but it will also have no issues.

mb1134 05-13-2013 12:31 PM

Do you think the Jcosta will make up for the top end loss if i switch to A-12. I believe i need a tad bit more low end power for these trail rides.

toomanytoys2 05-13-2013 01:31 PM

MB,

If a rise of only 1000' is really affecting your performance, I would tend to believe that you are too rich. A 1000' gain is really very small for a 4 stroke engine. When I take my buggy out to the desert, I see about a 3000' gain, and the only real difference that I see is the amount of choke I need to fire the engine (manual choke). This is on an 170cc BBK, with an A12 cam, PNP head, custom exhaust and redneck intake.

Johnny 5 05-13-2013 09:00 PM

I live at about 150ft above sea and when we go to the high desert 3000/3600 ft I notice the power is a bit lazy. With these small motors a little change is noticeable. We are going to the a place called Gorman in Hungry Valley CA. and the altitude is 3000ft to 6000ft. Probally wont go as high as 6000ft, but we haven't run the buggys there since the last time we were at 3000ft the motor was stock with 10g rollers and 1500rpm spring. Also compression was 125psi and now on both buggys have about 145psi. As for jetting I am going to leave the 127.5 in the blue buggy and the 122 in the red for now.

SYCARMS 05-14-2013 12:26 AM

I believe once you install the TK variator you will leave the cam you have installed.




Quote:

Originally Posted by mb1134 (Post 33321)
Do you think the Jcosta will make up for the top end loss if i switch to A-12. I believe i need a tad bit more low end power for these trail rides.


xlint89 05-14-2013 08:22 PM

Quote:

Originally Posted by SYCARMS (Post 33348)
I believe once you install the TK variator you will leave the cam you have installed.

Ooooohhhh, I wanna hear your review on that one. They look really interesting to me. :party:

mb1134 05-15-2013 08:06 AM

To bad. You are not allowed! cancel the party.

xlint89 05-15-2013 10:13 PM

Turn the lights out, the party's over........ :(

mb1134 05-16-2013 05:49 AM

I will give you a full review for some Browns tickets.

xlint89 05-16-2013 09:58 PM

What??? People really want those?????

bear 05-18-2013 09:04 AM

They make great gag gifts!!! lol

xlint89 05-18-2013 09:33 AM

:rofl: :rofl: :rofl: :rofl: :laugh2: :laugh2: :laugh2:

Now THAT was funny...... :D

SYCARMS 05-18-2013 09:37 AM

Kinda like asking for Cub's world series tickets!!!:banghead:

mb1134 05-20-2013 09:18 AM

Hey now! I stay true to my roots. Bear, you of all pople in Cincinatti should know my pain.

XLINT, maybe you should move to youngstown if you arent a browns fan.

bear 05-20-2013 09:31 PM

Ouch! lol

xlint89 05-20-2013 11:22 PM

Sorry MB, not much of a sports fan. I like playing them, but just sitting watching someone else play isn't fun for me. I'd much rather be out doing something like wrenching or riding.

I may go to an Indians game or 2, but that's about the extent of my spectating. And that's really more like a picnic if you ask me. oh, I need a beer. Now I want a hot dog, gonna go get some nachos, dam I want those peanuts..... :)

mb1134 05-21-2013 05:47 AM

That explains it Xlint. As far as going for the beer, im all for that. Although last game i went to, i was broke before i was buzzed :( I was at the infamous beer bottle throwing game. I for one did not waste my $8 beer.

SLESTAK75 05-22-2013 07:52 AM

No doubt. $8 beers are like gold.

SLESTAK75 05-22-2013 07:52 AM

But then so are $1 beers.

mb1134 05-22-2013 08:07 AM

Very true!!!!!

SYCARMS 05-22-2013 08:55 AM

Beer served at most sporting events is only 2% alchahol,a rip off for what they charge. I quit sporting events for the simple reason In the old days of baseball records were set in a 60 game season today they are set in well over 100 games while on steroids and are said to break the same record set in less than half the games . Quarterbacks played with broken pelvis's and ribs, today they are out 3 games for a bruised hip. Goalies used to take a puck in the face then skate to the bench never getting off the ice while the team doctor stiched him up. The other day I was watching I think Phillidelphia when the goalie got hit in his reinforces catchers mask and was taken out of the game for being shaken up. Sports today are played by overpaid P@ssies as compared to the early days. It has become the modern day collisium to keep the population passive to all the rape done by our polititians.

toomanytoys2 05-22-2013 02:05 PM

Tom,

I notice that you have a very passive nature about you when it come to professional sports :lmao:

SYCARMS 05-22-2013 02:11 PM

Thanks for noticing, I do pride myself on my passive nature:cussing::laugh2::crying::banana::banana::ba nana:

bear 05-23-2013 03:35 PM

And calm demeanor!!! lol


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