My first build, questions about bicycles and engines.

[vyzhion]

At first it wouldn't start. I eventually got it started and idling correctly. I decided to test it out in my neighborhood. I got it up to 25 mph no prob. I turned around to go home and i lost all power. The engine would rev but i wasn't moving. Almost like I was stuck in neutral. Could I have snapped the engine shaft or broken something in the gearbox already? Any ideas?

 

[5-7HEAVEN]

Vy, i'd say it's either the clutch or the gearbox.

the chain is still intact, correct?

the same thing happened to me on my maiden voyage with my MITSUBISHI engine/STATON gear chain install. one second everything's fine, then i'm in neutral with engine revving and no movement. i looked below me, and my drive chain was missing. i looked back 50 feet, and there lay my chain. the master link had twisted off, due to chain/gear misalignment.

after 20 minutes of searching, i found the master link and pedalled 4 miles home. after careful re-alignment, i reinstalled the chain and never had that problem again.

pull the gearbox. twist the engine connection by hand. if the end sprocket doesn't move, the gearbox is defective and needs to be returned.

if the end sprocket DOES move, then it's the clutch.

before yanking anything, start the engine and see if the drive chain and sprocket moves. if they do, then the freewheel is defective.

Myron

 

[5-7HEAVEN]

I jinxed myself.

on my last ride this afternoon, i stopped for a "whiz". left the bike idling. a few minutes later, i pull out on a very slight incline.

after a few seconds of throttle, i "hit neutral". looking back, i see my drive train laying on the road.

the master link is bent, as well as the adjacent link. i can't find the locking piece, so i tie the chain to the handlebar and pedal home for 2 miles.

darn. and i just lubed both chains and sprockets today.

Myron

 

[vyzhion]

Ok... I looked at this closely and the chain is still attached and intact (although it is much looser than it was when I originally installed it). I pulled the cover off of the gear box and everything seems intact here as well. I can turn the gears freely in both directions but it does not turn the drive shaft. The shaft jumps slightly as if it is about to move but then goes back to it's original position. I am guessing this means that the clutch is not engaging as it should?

 

[Butch]

Just a guess but sounds like you might have sheered a key holding the clutch.

 

[vyzhion]

ok ok ok... time for an update on this project. I received a replacement engine gearbox from the vendor and have just recently succeeded in killing that JL hoot figure 8 style gearbox as well. I used gear lube in the gb like the vendor recommended but it always leaked out of the hollowed out bolt on top of the box. Anyhow it still lasted only a few months of actual use. I pulled it apart today in preparation of installing the Grubee Skyhawk 2 gb I just received. The teeth on the gear attached to the clutch bell were sheared almost completely down on one side and there were metal filings and debris in the gear lube. Odd no? Anyhow I have had now 2 bad experiences with these JL hoot style gearboxes and I warn anyone that considers buying one to stay away. Spend the extra money and get a Grubee kit or a Titan. I am installing the Grubee this week and I hope to have better luck until I can save up for a titan. I have decided to try to pack the new gearbox with grease and see how that works because I got really tired of the old gb leaking all the time. If necessary, I will use oil and seal the thing with gasketmaker but I am hoping that the grease will do the trick. Wish me luck. I'll let yas know how it goes. :???: