[TheNextSpies]

like the title says. what do most of you do to the crf 100 engines to get more power out of them?



what exhaust?

what do you do to the engine?

what size carb?



any other details?

 

[chasetheface123]

Budget? 145 superhead....

 

[TheNextSpies]

i whould have to ask my dad about that but the class limit im racing in is 110cc

 

[firepower354]

Budget will dictate parts list...



At the least, plan on an oil pump, filter (remote or CB50R, Kitaco/Tak if the budget permits). Lightened flywheel helps the slug rev.

 

[taz69]

If you are trying to road race it with SEMRA.. There isnt much you can do a CRF100... You will get out powered by the 50 bikes.. They weigh a lot less and at 110cc can make 10 to 14 hp.. Not sure there is a 110 kit a CRF100 and if there is it wont make 14 hp and the 50s will always weigh less... Thats why a lot of guys in SEMRA anyway dont race CRF100s they go for CRF50 sized bikes.. Plus the 50s handle WAY better...

 

[firepower354]

I dunno, might be fun to try. How aboot a 58x41.5 on an 80 bottom, with a stage 3 Tak roller head? In an early XR75 12/12 bike? Only one on the grid

 

[taz69]

Yea XR75 as a 12/12 setup would be little better than the CRF100 and with an engine like that it would be the only one...

 

[TheNextSpies]

no ill be racing with tmgp and cmra

 

[TheNextSpies]

which will be more valuable? the 110 kit from powroll or a takegawa superhead? with a pro circuit pipe and a atv carb with a pod filter

 

[firepower354]

The head is worth WAY more power than a few CC's. The darn 115 kits won't help you,unless you de-stroke a tad. Or... Use a 58MM Tak piston and early 41.4mm crank. 109.6cc and a ton lighter crank. Gotta make a few little mods, but it's a sweet setup.

 

[TheNextSpies]

The head is worth WAY more power than a few CC's. The darn 115 kits won't help you,unless you de-stroke a tad. Or... Use a 58MM Tak piston and early 41.4mm crank. 109.6cc and a ton lighter crank. Gotta make a few little mods, but it's a sweet setup.

thanks for the advice. can you buy just the superhead or do you have to buy the 115 kit to get the head?

 

[firepower354]

Nope, you can get just the head. You'll still need a piston, but that's pretty easy.

Stage 1 head - $380

Stage 2 head - $460 adds Ti retainers

Stage 3 head - $590 latest roller cam bearing version, bigger valves

 

[TheNextSpies]

Nope, you can get just the head. You'll still need a piston, but that's pretty easy.

Stage 1 head - $380

Stage 2 head - $460 adds Ti retainers

Stage 3 head - $590 latest roller cam bearing version, bigger valves

awesome. one more question where can i look at the different heads and options? and does getting the head require the other stuff you said above?

 

[1/4 chub]

you should check with your local club and see what people are using in the class you want to ride in.if there all running 50 based bikes on 10's your not gonna be competitive no matter how much money/effort you put into a crf100

 

[TheNextSpies]

you should check with your local club and see what people are using in the class you want to ride in.if there all running 50 based bikes on 10's your not gonna be competitive no matter how much money/effort you put into a crf100

with tmgp its all built 100s and some 110s

 

[firepower354]

awesome. one more question where can i look at the different heads and options? and does getting the head require the other stuff you said above?

The Tak head won't require much more than a suitable piston for the larger chamber. The lighter bottom end is just an option.



There are likely better versions of the Tak catalog out there, but here's one:

PARTS CATAROG vol.21 2009-2010

 

[TheNextSpies]

thanks hopefully i will be able to get that for my bike

 

[ap3x]

trail bikes has a 132 kit for the 100 and it's pretty inexpensive.

 

[connorpb7]

terry would you be able to provide a suitable piston?

 

[firepower354]

terry would you be able to provide a suitable piston?

Does a Hobby Horse have a hickory....

Yeah, I can come up with some thing. Akunar has a decent 55.5mm with a 14 pin for the 110cc limit class. Heavier than I'd like, but fits the bill and doesn't require much valve notch work.

Swapping to the lighter 41.4 crank and 58mm bore (light Tak piston, 13mm), tighter gearing might be a good way to go, unless it's gotta be a bolt-on affair. That 100 crank is a big 'un.



Edit* Oh, I said that up the page a ways... Still.