First engine build

[bob58o]

These engines are pretty simple so they are fun and easy to modify. But they also get expensive. So If you enjoy building the engines, like me, these are great. If you are looking at max performance per dollar spent, then a bigger engine off a wrecked bike or something would be cheaper possibly. You could easily dump $800 into a clone and get maybe 15-20HP but it will be less reliable than a bike engine designed to spin 8000 RPM.

That being said, I like modifying clones because I know how to. I know what parts fail. I know where to buy parts. I know who to call to ask questions.

 

[OzFab]

I hear what you're saying OzFab, that being said I'm still going to build myself an engine. Just something I've been wanting to do for some time. Not disagreeing with you by any means, what you're saying is completely valid. Maybe I'll regret it down the road, but for nothing else I want the experience of it.

That's fine, I was merely guiding you by answering your original question; I always say the best way to learn is to do...

 

[Truax]

Thanks again the guidance gentleman, really do appreciate this forum. Got most of my goodies in today. Also threw together this little harbor freight work bench tonight. I wonder what the girlfriend will think of me replacing the kitchen table, I really need to get a place with a garage...

 

[esfoder]

Easiest way to get more torque is a bigger pump. You have some classy parts there. Lookin good.

 

[bob58o]

Easiest way to get more torque is a bigger pump. You have some classy parts there. Lookin good.

Well I'm going to have to agree with OzFab... The EASIEST way to get more torque is through gearing.

You are correct. A 390/420cc might have double the torque of a 200/212cc. No replacement for displacement (cept maybe N20 or a blower).

But if you want Low end and High end, you have to gear em low and spin em high. Or just wait for Santa to bring that transmission I asked for.

 

[SammyCat]

ya just need some neato spark plugs to get more torque.

 

[Truax]

Well everything went fairly smoothly with gutting the bottom end. Just finished installing everything, with the exception of the heavier springs, it's recommended to break-in the cam with the stock springs I guess. Have to run out of town for the second job, but come Saturday I'll have my Moment of Truth and see if she doesn't explode. Stay tuned maybe it will.

 

[bob58o]

but come Saturday I'll have my Moment of Truth and see if she doesn't explode. Stay tuned maybe it will.

You may be disappointed to find out that we live to see the carnage. Fingers crossed. Not going to say what I'm wishing for. JK

 

[Truax]

Well carnage of sorts. Got a half dozen quarter mile sprints in and the bronze bushing in between the sheaves of the drive clutch blew apart. Probably a little too much for Chinese 30 series to handle. Thought I could get away with some heavier springs and a Comet belt, but I'm not going to replace failing parts every ride. May have to go back to the drawing board and figure out a better transmission of power to that big 20 inch tire I got in the back....

I through it in a modified Coleman CT200u by the way. Thing really was ripping and tearing for the short while before the fail. Is there any of these nice race clutches with sprockets for heavier chain than 35? Maybe I'll trying a race clutch with the stock jackshaft setup,. I'll keep tinkering and keep you fine folks posted. As always, any advice is much appreciated.

 

[Truax]

Replaced the bushing with a genuine comet part and it's holding up for now. Also adjusted the preload in the driven unit and dropped down one tooth up front. Seems to be holding up a lot better, time will tell I suppose.

https://youtu.be/AkThHvIAqEI