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  #1  
Old 04-12-2015, 10:41 PM
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toomanytoys2 toomanytoys2 is offline
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Default Fun, and not so much fun and games

Let me start this thread my saying - NEVER EVER ASSUME ANYTHING. It's been awhile since I have been here and my poor HH had sat for a little over a year. Well it came time for our annual week in the desert, so I pulled out the HH to make sure it was ready. 1st discovery was the carb was shot (damn Ethanol), so I picked up the quickest carb I could get, and also a manual petcock. It ran good for about 20 minutes, then it would hardly run. I checked the spark numerous times - nice and blue and could even hear it crack, so I wasted about 5 hours playing with the new carb and checking the coil and CDI. To make a long story short, I had about given up and the HH wasn't going to make the trip, but at a spur of the moment, I remembered that my wife's dirt bike used a very similar spark plug. Swapped it out - and success. I have worked on many different engine types, but I had never seen a sparkplug act so well, yet didn't let the engine run.

So loaded up and headed to Gorman. Had a great time, but on the next to last day, my daughter and I went for a long journey in the HH. We really put it though the paces, and were gone for almost 3 hours. Wide open sand washes, tight almost single track, you name it. However, the first thing that reared its head, was that after going into reverse, it wouldn't shift into forward. I carry tools, so I dropped the idle to see if that would help (nope). At one point, we were afraid that we would have to limp back to camp in reverse. Finally got it into forward and started back, (I could use some tips on this, it's an external reverse).

Then heading home, we had a long uphill pull to go up. We could see camp and it was about 40' to our turn off when the engine started losing power and died. Jumped out and started looking for problems. Didn't see anything, so jumped in and tried it. It fired went about 6' and died. It acted like it was running out of fuel. So we sat for a couple of minutes, fired it up and creped towards the turn off (multiple times). Finally once we made the turn off, it was down hill to the camp, and once the HH fired, it ran fine back to camp.

So I ASSUMED that the problem was with the new manual petcock, not letting enough fuel through, so I pulled the fuel filter off and just ran a straight gas line. The next day, me and my son took off. We got about a mile from camp, and on an uphill it did the same thing. This time the starter went click. I jumped out and tried jumping across the solenoid - no good. Luckily we were by a camping area, so I was able to get a jump - still no good. So I figured I toasted the starter. I always carry a tow rope and the person that jumped me gave me a tow back to camp.

Back at camp, I pulled the starter, and it spun fine, so I pulled the fan housing off, and it looks like I seized a piston (can rock the crank, but that's it). All in all a fun trip, however, when trouble shooting NEVER ASSUME ANYTHING
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2005 Hammerhead 150
170cc BBK, PnP Big valve Head, A12 Cam, Uni Filter, Custom Exhaust, 10G rollers, 1500 Contra Spring, 2000 Clutch Springs

Just added - 2007 Joyner 250 SV - Let the fun begin

4-Dirt Bikes, Baja Bug and enough toys to keep me in the garage and out of trouble.
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Old 04-13-2015, 10:55 AM
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Sometimes blowing out a CVT drive belt will wedge the variator and hold the crankshaft. Pull the CVT cover and see if your belt is still in one piece or if it is shredded.

If you ran OEM carburetor jetting with your mods, you were running too lean and most likely damaged the piston and cylinder.
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Old 04-13-2015, 12:54 PM
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I actually, swapped the jets from my old carb to the new. Also, Gorman is 3000' higher then my home elevation. However, that doesn't insure that I wasn't running lean. In fact, that is what I am expecting and will be my first thing that I check when I start the tear down. The plug and the combustion chamber will give a good indication on that aspect. Who knows, could be a manifold leak or something along that line. It will probably be a month before I tear into it, then I can find out.

Any tips on the forward gear not engaging right (external reverse)? I tried searching, but most people seem to have a problem with reverse.
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2005 Hammerhead 150
170cc BBK, PnP Big valve Head, A12 Cam, Uni Filter, Custom Exhaust, 10G rollers, 1500 Contra Spring, 2000 Clutch Springs

Just added - 2007 Joyner 250 SV - Let the fun begin

4-Dirt Bikes, Baja Bug and enough toys to keep me in the garage and out of trouble.
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Old 04-13-2015, 02:18 PM
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Quote:
Originally Posted by toomanytoys2 View Post
I actually, swapped the jets from my old carb to the new. Also, Gorman is 3000' higher then my home elevation. However, that doesn't insure that I wasn't running lean. In fact, that is what I am expecting and will be my first thing that I check when I start the tear down. The plug and the combustion chamber will give a good indication on that aspect. Who knows, could be a manifold leak or something along that line. It will probably be a month before I tear into it, then I can find out.

Any tips on the forward gear not engaging right (external reverse)? I tried searching, but most people seem to have a problem with reverse.
Is your cable attached too tight or maybe too loosely ? Do you have a picture of your gear assembly ?
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Old 04-13-2015, 02:54 PM
tkeagle tkeagle is offline
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Have enough grease in the box? Maybe was locked in reverse because couldn't slide back into its normal poisons which is forward. You was playing in fine sand right? Maybe some sand was not letting it slide in and out like it should? Just a few thoughts.
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Old 04-13-2015, 03:51 PM
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This is my gear box. If I understand it right, when reverse is selected, the fork #11 pulls the #10 assembly out until the Planetary gears engage the drive gear #9. This would then engage reverse. Once the lever is moved to forward, it looks like spring #12 is supposed to move the gear assembly #10 inward (past the Planetary gears) and engage 9 into the inner teeth of #10. If this is true, then I either have a lubrication issue, or a spring issue. There is slack in the cable, when forward is engaged and like I mentioned, I dropped the idle speed considerably.
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2005 Hammerhead 150
170cc BBK, PnP Big valve Head, A12 Cam, Uni Filter, Custom Exhaust, 10G rollers, 1500 Contra Spring, 2000 Clutch Springs

Just added - 2007 Joyner 250 SV - Let the fun begin

4-Dirt Bikes, Baja Bug and enough toys to keep me in the garage and out of trouble.
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Old 04-13-2015, 05:54 PM
liduno liduno is offline
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If the idle was too high when switching gears it can deform parts 9 and 10. That can keep 9 and 10 from sliding in and out.
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Old 04-14-2015, 01:44 AM
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toomanytoys2 toomanytoys2 is offline
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Never did have a "High" idle when driving the buggy, when I dropped the idle down, it was almost to stall speed (before I seized it ), so for now, I am ASSUMING that it is probably causing problems from lack of lube, maintenance and grit.

Right before the trip, I was talking with X-bird on the phone, and we were talking about how having toomanytoys can keep you from concentrating on just one. Anyone catch the pun
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2005 Hammerhead 150
170cc BBK, PnP Big valve Head, A12 Cam, Uni Filter, Custom Exhaust, 10G rollers, 1500 Contra Spring, 2000 Clutch Springs

Just added - 2007 Joyner 250 SV - Let the fun begin

4-Dirt Bikes, Baja Bug and enough toys to keep me in the garage and out of trouble.
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