Author Topic: Who knows pit bike engines?  (Read 1903 times)

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Offline Scott S

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Who knows pit bike engines?
« on: August 07, 2015, 06:31:15 AM »
 A while back I bought this '71 CL70. Did a bit of a "rustoration" on it and had the original engine built out to 117cc. That was a fiasco....it blew up three times and I pushed the bike to the back of the garage.

 My original plan was to do a pit bike swap. I'm getting the itch to do something with it again. I'm leaning towards a Piranha 140cc, a.k.a. the YX 140 engine.
 I read about upgraded carbs, bigger exhaust needed, charging system, etc. Then there's the whole converting to 12V and CDI thing. Splice into the existing harness or just swap in a complete new harness? And what about an oil cooler?

 I'd like to be able to cruise easily at 45-ish MPH and occasionally hit 50-60 for short stretches when needed. I've already installed a 46T sprocket on the rear and, if I remember correctly, I was using a 17T up front.

 Can any of you walk me through doing a swap that would be kick only but still run lights for the street? The CL70 is titled and is street legal. I'd like to be able to eventually go out and beat up on a Grom. Or at least give them a run for their money!


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Offline vfourfreak

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Re: Who knows pit bike engines?
« Reply #1 on: August 07, 2015, 08:01:39 AM »

Offline Bailgang

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Re: Who knows pit bike engines?
« Reply #2 on: August 07, 2015, 02:46:35 PM »
I'd like to be able to eventually go out and beat up on a Grom. Or at least give them a run for their money!

+1, excellent idea. :)
Scott


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Offline faux fiddy

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Re: Who knows pit bike engines?
« Reply #3 on: August 09, 2015, 05:03:38 PM »
There is a site devoted to lifan swaps, mostly  ct's.

There is also chalopy.blogspot.com which I can't seem to pull up on this computer. It is good for ideas. Lots of project threads.
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Offline FrankenFrankenstuff

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Re: Who knows pit bike engines?
« Reply #4 on: August 09, 2015, 05:54:15 PM »
I've got an s90 with the same daydream of racing around. I saw a cool "twin" s90 motor project. Good luck, I am following this for any tidbits of power for horizontal single .

Offline Terry in Australia

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I was feeling sorry for myself because I couldn't afford new bike boots, until I met a man with no legs.

So I said, "Hey mate, you haven't got any bike boots you don't need, do you?"

"Crazy is a very misunderstood term, it's a fine line that some of us can lean over and still keep our balance" (thanks RB550Four)

Offline vfourfreak

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Re: Who knows pit bike engines?
« Reply #6 on: August 10, 2015, 02:47:18 PM »
Or check out Takegawa "special parts". Crazy stuff available for deep pockets. I had a dry clutch conversion of theirs, really excellent quality.

Kev

Offline Lostboy Steve

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Re: Who knows pit bike engines?
« Reply #7 on: August 18, 2015, 04:17:09 AM »
I have an 88cc 4speed Lifan on my z50 and it has plenty of power and speed with stock rear gearing. I mean it really goes. stock pipe with not much of a baffle left as it rusted away inside.


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Offline FrankenFrankenstuff

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Re: Who knows pit bike engines?
« Reply #8 on: August 20, 2015, 09:32:21 AM »
Have you seen the mini superchargers and mini turbos? I think about finding one of them for my little single.

Offline Terry in Australia

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Re: Who knows pit bike engines?
« Reply #9 on: August 21, 2015, 02:54:32 AM »
Have you seen the mini superchargers and mini turbos? I think about finding one of them for my little single.


Damn, now I want a mini supercharger.............. ;D
I was feeling sorry for myself because I couldn't afford new bike boots, until I met a man with no legs.

So I said, "Hey mate, you haven't got any bike boots you don't need, do you?"

"Crazy is a very misunderstood term, it's a fine line that some of us can lean over and still keep our balance" (thanks RB550Four)

Offline vfourfreak

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Re: Who knows pit bike engines?
« Reply #10 on: August 30, 2015, 11:22:21 AM »
Have you seen the mini superchargers and mini turbos? I think about finding one of them for my little single.


Damn, now I want a mini supercharger.............. ;D

There is really no limit to the great schidt you can get for these bikes. Unless of course you include prudent fiscality which exists for people who believe they will live forever.

Kev