Engine replacement for my CRF 70

[rooster484]

I just picked up a CRF 70 with some engine issues. I'm thinking about just putting something new in it. What would be recommended to replace the stock engine. I can't find much on ebay for used CRF engines.

Also, I'm of course willing to put something bigger in it if it will fit.

thanks,
Jeff

 

[Georgalis]

Gpx 124 , they are super cheap and I've seen them run good

 

[my67xr]

Welcome to Minirider's.

Drop in here and introduce yourself when you get a chance, post up a pic of your bike too if you can.

Do you want to keep the genuine Honda engine ?
If so you could rebuild the top end and fit a big bore kit, better cam, carby, race head and better exhaust etc
The big bore kit's can turn your 70cc into an 88cc, a 108cc and will be a lot more fun having the extra cc's.
Being in the US Tbolt might be the best place to go-
TBParts - 88cc Big Bore Kit fits Honda XR7/CRF7 Engines - TBW929 - Big Bore and Stroker Kits - Pit Bike Engine Parts - TBolt USA, LLC

TBParts - Race Head, 88cc Big Bore and 2mm Carb Kit for Z5 CRF5 XR5 CRF7 - TBW936 - Big Bore and Stroker Kits - Pit Bike Engine Parts - TBolt USA, LLC

TBParts - Roller Rocker Race Head V2 18cc Big Bore Kit XR7 & CRF7 - TBW919-XR7-CRF7 - CRF7 XR7 - TB Parts - TBolt USA, LLC


Your other option is a china pit bike engine, they'll all fit, something like the Lifan or YX125cc, GPX125 (125HO), 140cc, 150cc, 160cc
I reckon the 125HO might be the best bet for you, they have plenty of power and can keep up close to a 150/160 pit bike.
You can also upgrade the engine later, more cc's and better head, carby (OKO 26mm) etc etc
Engines - TBolt USA, LLC

With the bigger engine's you will probably want to look at upgrading the suspension, brake's handlebar's etc etc


Cheer's, Craig

 

[rooster484]

Thanks for the info!
Jeff

 

[headsmess]

stuff the biggest engine in that you can find!

but me myself have a particular liking for the lifan 125 (1p54) or the 140 with the "start in any gear" clutch...

do have to be careful as the bigger engines are slightly longer in the cylinder area, may hit front wheel... or get pretty close!

then the carb and manifold can cause major headaches.

keep the honda in the shed, adds value if you wanna sell it at a later date.