[Danman2540]

What are the sizes of the valves in the BVH that everyone is putting on their engines? Also I have a 3 valve head on my CRF110 Lifan engine, anybody have any info on these? It seems strong but I've never ridden a 2 valve 110cc. Also what transmission pattern is best in the Lifans? I ask all of this because I'm considering a 125cc Lifan. Please tell me what you know.

 

[joman2055]

i think you should go with one of the new 4 up 140cc lifans.

 

[Danman2540]

I considered one of those too, they're just new and not proven yet and I'm not sure I want to have to have an oil cooler. How much can those be had for now anyway?

 

[firepower354]

I considered one of those too, they're just new and not proven yet and I'm not sure I want to have to have an oil cooler. How much can those be had for now anyway?

$350 shipped. Toss on a $60 IRK and a $50 piston. She'll rip!

 

[HACKMUNCH]

oh ya they rip untill that ci cylinder gets hot them there goes the ring tolerances. so they rip for about 1 hr or so.

 

[vetmxer]

ya if ya wanna run the stock harley style cyl. you have ta run it like a harley. loose ring oil burner.stock they have a boreXstroke ratio like a harley i couldnt help it.

 

[firepower354]

Pro-Stock 500 inchers run iron blocks too, not just Harley-Fergusons, who stopped using iron jugs 23 years ago.



Despite it being (much like myself) big heavy and ugly, isn't cast iron (unlike myself) much MORE stable than a thin steel sleeve pressed in an aluminum jug? An overhanging piece of center case gasket and a tiny bit of case material was enough to push on a 146 sleeve and tighten the bore on the piston enough that it wouldn't turn over by hand near BDC. I had to scrape a few thousandths out of the OE GPX case, hanging the engine topend down. That and the closeness of the stud holes seem like a stability issue. Anyone done a leakdown test on a new and run-in 146? Gapless rings being tried?

 

[Danman2540]

any help on my original questions?

 

[RcWannabe]

I wouldnt get a lifan 125 the 120 costs only slightly more and is a much better engine.



125 = Cast iron cylinder, crank mounted clutch, No really easy mods available also doesn't have the big valve head



120= Trans mounted clutch so it is capable of running an inner rotor and starts in any gear, aluminum cylinder, has the good head that everybody is using, and plenty of bolt on kits and mods you can do. (The head is 27/23 valves to answer your other question.



The 120 can be had for 300 shipped on ebay, the only issue is there may be false neutrals but you can fix that with a 32 dollar part from sdg.

 

[Danman2540]

well this one says it has the 27/23 valves, is this it? are they just calling it a 125cc?



eBay Motors: CARB Lifan 125cc Motor Engine XR50 CRF50 XR 50 70 CRF70 (item 230135094129 end time Jun-04-07 19:30:00 PDT)

 

[vetmxer]

it looks like a big valve head,crank mounted clutch engine. i couldnt tell ya the displacement.