CRF Specs
 

Can anybody confirm if these timing figures are correct???

Induction:
Opens 15º ABDC
Closes 70º ATDC
Total induction 235º

Total Transfer: 124º

Total Exhaust: 172º

What's the bore and stroke on this engine???


AFM

head shim
 

hi my name is brett i just recieved my new crf 12 i'm running 16% fuel what head shim do i remove.I live in Brisbane Australia where we have a hot and humid climate can anyone share some info. :cool:

Have a buddy that just got a Wasp to fit into hes G4S.
Any guys have recommendations for gearing the G4S with the Wasp.
Some guys have said that they cant gear down enough to get the bottom end responsive enough.
Any ideas or recommendations welcome.

Here you go, official CRF gearing for the G4S :

-1st gear 18/52
-2nd gear 23/47

For the bottom end, the original clutch does not suit the engine well, you need to get our special clutch parts set. I have a G4S and the car flies with this engine :nod:

Nano

The lateral play is very normal and a little vertical can also be felt. It will be ok once you install the flywheel and make it tight.

Nano

Thanks Nano

We ran 18/52 23/46 ,car ran well.
Buddy managed to TQ and take the win in the A mains.
Engine ran a bit hot but it hadnt had more than 8 tanks through it by the finals.Sure there si more in there.

is it normal for these engines to run 300 deg im running 30% fuel after a 20min main my temp is at 300 but the engine has lots of power at that temp the only problem is when the engine get to idle it bogs really bad when i try to take off is this my clutch or is this engine tune and i have it on a mtx4 with the crf clutch

What is the best gearing for a Mugen MTX4. I tried mine this weekend and I was very pleased

If you hear the deep "waugh, waugh, waugh" sound and your car doesn't go anywhere, it means that your low speed needle is too rich. When my engine runs at 300F, it's a missle, but I know that the high speed needle is a bit too lean. Clutch setting and 2nd gear shift point may also impact your temps, but if your clutch isn't slipping and your 2nd gear is shifting correctly after the engine has warmed up properly (3min), then it may just be your settings.

Some info posted by Brian Kinney may be helpful if you haven't already seen it:

- http://www.rctech.net/forum/showpost...&postcount=608

Hope this helps :)

Nano can you give me your clutch settings for the g4s?? Thanks a lot.

I don't remember exactly the setting because my engine and clutch are in parts right now and I haven't had time to run the car in a while.

One thing though is that when using the CRF clutch parts on the Team Magic, the nut that tightens the flywheel on the engine shaft is too short and that can cause problems with the clutch function. You want to add a spacer between the nut and the flywheel. This way you can tighten the spring adjust nut without making the spring too tight. I used a spacer that was 0.8mm thick. Then the spring adjust nut was tighetened about 0.5mm lower than the edge of the flywheel nut.

Hope this helps!

Nano

so should i have it to shift early or close to 1st gear is out

You don't want it shifting early. ;)

hi guys whats the recomended shims for the CRF if you are running 20% ?

Great newz and bad newz, can you say balestic?? I got the engine going even better than before, crazt fast talking 1/8 speed on our club track no lie. Glad so many other are afraid to run this engine from what they hear and the make, only give me the advantage ;) . But one thing, engine kept shifting and was blowing gears in my RRR. Anyone else having this problem? I try with and without locktite but to no avail. I am to give it another go today. Big trohpy race sunday, and want to be ready.