QT50 Clutch Springs

I put the stiffer springs on my QT50 yesterday but it seems like the takeoff on the bike is worse. It definitely revs at higher RPMs to start but instead of getting a noticeable takeoff when the clutch engages it just slowly accelerates up to its top speed. With the old springs, once you got up to 5-7 mph there was a definite jump, but now nothing. Just smooth up to 35 or so. My question is has anyone had anything like this happen? Does this sound like a case of the springs being too tight? Is this the clutch slipping? I have 5w30 in it right now, which I know isn't the recommended but I was also running that oil on the old springs without problems.

Thanks in advance.

Re: QT50 Clutch Springs


Anyone who has modified springs on any bike have a similar experience? The old springs were fairly easy to manipulate but the new ones are not just a little bit, but a lot stiffer than the old ones.

Re: QT50 Clutch Springs

My hole shot springs work likw a charm. what other mods have you made to your bike?

Re: QT50 Clutch Springs

So far I have the pw50 gearing, k&n filter, and boyesen reeds and was working great before. While I was working on it I also replaced the two seals on the top end. Both the one between the head and the cylinder and the one between the cylinder and crankcase. I put a new crankcase seal on as well.

Here is another thought. I did remove the piston rings and cleaned the grooves. There did not appear to be any damage to them but it was the first time I've taken the engine apart to that extent so it is possible I did something wrong in reinstalling them. The shop manual wasn't too clear about the specifics of the process. Would improperly installed/set rings cause what I am describing, high rpms with little acceleration/power throughout? I don't have much experience with anything like that but could it be caused by air escaping around the edges of the piston?

Re: QT50 Clutch Springs

Every time you remove the cyllindar the rings have to reseat causeing a temperary loss of power.

Re: QT50 Clutch Springs

Thanks, I will break them in again. Hopefully I will get power back. I wouldn't have expected such a dramatic loss of power I guess but it seems like that could be the problem rather than the clutch.

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