Cr85 or 150r

[fast shee]

Looking to build a mod this winter for my son who will be turning 8 this fall and looking for some recomendations on which engine to use. He races enduro and will be competing against riders 9-12. I have located a yamaha blaster widened and lengthened. To me it looks like the perrfect donor for the build. Keeping in mind that he may not run it until later in the season until he gets used to a shifter. He runs a drr90 now and handles it quite well and know the 2 engine options produce much more power so there will be a major learning curve. Of the 2 engines which would be the better of the 2 for fit, performance, and rider friendlyness?

[djdfairchild]

unless your classes are different it will be a while until he can race the 150, here you have to be 12 i think. but the 150 is a much better motor

[fast shee]

He is moving up classes early and they allow 150cc 2 or 4 stroke. Just have not heard much about the 150 in a blaster chassis. Most kids are running pitster pro bikes with cr85-100 engines or raptor 125. The raptor 125 looks really under powered even with engine mods. This is why i am leaning towards the 150r engine. If anyone has put the 150 in the blaster chassis and reads this maybe they can shed some knowledge on this project for me.

[Logan #34's Dad]

1st, make sure you would be allowed to run a non-production machine with the rules set by your organization.
2nd, the 150R engine would be an awesome powerplant for that type of racing (assuming that enduro racing is woods racing). It puts out double the power of the engines you stated. The 4stroke would be much easier than the 2stroke to manage through the slow stuff. The low end grunt would help.
If your allowed a "modified" machine.....You may consider using the Raptor125/250 chasis with the 150r engine. The chasis geometry has gotta be better than the Blaster and there are a ton of aftermarket parts available for the Raptor....

[fast shee]

We are allowed to run this setup as there is 2 of them running it now. Enduro is woods racing and is the main reason i am leaning towards the 150. Not sure of the geometry difference of the raptor vs the blaster chassis. There are very few on the market up here aand if there is one it is a stocker. The blaster i found is already setup with everything required. Just need to do the transplant. Seems that most 150 setups are on chromoly chassis and no other manufacturer frame.

[qcitytile]

I have seen them in 250r and 450r chassis.

[tyler70t]

Let me know how this works out. Tyler wants to go with a 4 stroke next year and the 150r is what I am leaning towards, our chassis is a blaster as well ....................Jeff

Post pics if you can

[fast shee]

Originally posted by qcitytile
I have seen them in 250r and 450r chassis.

For my sons age he is not ready for a full size chassis. Hoping the blaster or raptor chassis would be adequit.

[fast shee]

Originally posted by tyler70t
Let me know how this works out. Tyler wants to go with a 4 stroke next year and the 150r is what I am leaning towards, our chassis is a blaster as well ....................Jeff

Post pics if you can

If i get the info i need to start the build i will keep you informed. The 150 powerplant is a sure thing, just have to make up my mind on the chassis. I like the aftermarket selection of add ons for the raptor but a complete built bike would save lots of $$$$.

[camspawpaw]

I just finished putting a CR85 motor in a DRR90 frame, this thing is a missle! I made all brackets and gussets, re worked swing arm to accept sprocket on the opposite side a few other changes and it is done, easy inexpensive mod!!! My Grandson who is 9 LOVES to ride this beast.