Which Race Cam??

[andy600rr]

Sweet. Time to start doing some more on-line shopping then!! (If I can remember my password for ThaiEpay)

Have you had a chance to check the duration on the stock cam yet?? I'll most likely pop a Z40 in mine but might use the standard 140 cam in a 125 clutch on crank Lifan I have in another bike since it sounds like its at least going to have a higher lift than the standard 125 cam (1P54FMI).

 

[Mack]

I started mapping the valve timing and only got the inlet done, it's written down at the workshop, but around 180 degrees at zero lash. Probly same for exhaust. Honda cams won't go in this head so you can forget the Z40. The cam is the long style import. I am working on a new grind for these.

 

[andy600rr]

Ah ha. Thanks for the info. My motor's sitting in a box waiting for me to tear into it. Been doing a lot of sitting around lately with a broken leg but should be back on 2 feet and working on the mini's soon.

Thanks for the heads up on the cam.

 

[rovaza]

Hi, just new on this Forum.
I`m from The Netherlands and selling and repairing 4-stroke mini bikes.
I just got some news from a dealer in Sweden that the DRP Z40 cam gives 17,39 HP ! In a 140cc Lifan engine with a 28mm PWK carburator (115 Main Jet and 45 Slow Jet) Further the engines was normal. (In a Pitbike)

I think that is very nice.

Best Regards
Roald

 

[Cactus Jack]

I started mapping the valve timing and only got the inlet done, it's written down at the workshop, but around 180 degrees at zero lash. Probly same for exhaust. Honda cams won't go in this head so you can forget the Z40. The cam is the long style import. I am working on a new grind for these.

So what have you come up with for the 140 cams ? The long Lifan small valve head 120 cams are 72 mm long (from sprocket face to outside of the small bearing) and the short Lifan 110 E22 head cams are 65 mm measured from the same points !

 

[Mack]

Well I have what I think should be a very good cam designed for this engine on paper but are still trying to get a master cam made. Not cheap. In the meantime, I lost a little interest because guys are fitting Honda cams by doing a bearing swap and also there is still a good supply of G2 cams and similar in the long import style and short for this head. Just have a look at tbolt TboltUSA. Welkom to Rovaza can supply the Z40 and R20 + springs and is the best option IMO for max power.

After mapping the stock cam I found the exhaust lobe has a much bigger profile than the inlet. So for the budget guy who wants a little improvement you could try having the inlet lobe hardwelded and ground to the exhaust profile by using another stock cam as a master. Another option is to send your cam off to somewhere like Web Cam Inc - Performance and Racing Camshafts and have them grind you a cam.