Yfm350 serious power build!!

Yamaha Raptor 350 & Warrior Forum

Help Support Yamaha Raptor 350 & Warrior Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Kinda like to talk carbs again, lots of recommendations to upgrade. I kinda liked some things I heard about the FCR 37MM earlier in the thread. Basically to put one on I'd need a Rappy350 intake boot & rappy 350 airbox to carb hose or whatever right? You ya use the Raptor throttle linkage too? Are they worth the$200+ I saw em goin for on ebay?
 
Hmm, makes me wish I had a combustion chamber ccing kit. I guess it's simple really, a piece of clear plexiglass with a hole to add some sort of colored water & some petroleum jelly to seal it, heck, you could prolly even use an old sringe for the volume as long as ya kept track of it, it'd just take more time. Oh....yeah, this has turned out to be a good thread, I'm proud to be a part:)

I feel if you go 85mm or larger....you should dykem (blue) the head and
attach it to the jug off of the case....scribe a circle and radius the chamber
to that.
CC the chamber when you start...and when you are done....you are looking to remove 3 cc's or better....the radiused chamber will give better quench.....
One thing i know about JE and Wiseco is that the CNC program they use for the dome is the same for any bore size....
A bigger bore will have more compression....soooo....relieve the chamber to go along with it.....
I bet if I went to a 12:1 piston with a massaged chamber and .430 webcam it would run just fine on 93 octane....

Jebby
 
Last edited:
I feel if you go 85mm or larger....you should dykem (blue) the head and
attach it to the jug off of the case....scribe a circle and radius the chamber
to that.
CC the chamber when you start...and when you are done....you are looking to remove 3 cc's or better....the radiused chamber will give better quench.....
One thing i know about JE and Wiseco is that the CNC program they use for the dome is the same for any bore size....
A bigger bore will have more compression....soooo....relieve the chamber to go along with it.....
I bet if I went to a 12:1 piston with a massaged chamber and .430 webcam it would run just fine on 93 octane....

Jebby

I'd like to see that done Jebby, I personally would be a lil scared b/c the valves are so close to the edge of the chamber. Do you have any pics?
 
Youd end up running race fuel and would only be saving the cost of a bore job. The jug would have to still be honed.

I'm strongly considering it man, I've honed the jug, it looks good & I feel confident with it. I prolly will have to mix some 93 with some 110 but that might be ok. I guess there's only one way to find out, I've polished the chamber pretty nicely to help prevent pre-detonation. Also gonna run the Web .430 I think. We'll see what happens.
 
I feel if you go 85mm or larger....you should dykem (blue) the head and
attach it to the jug off of the case....scribe a circle and radius the chamber
to that.
CC the chamber when you start...and when you are done....you are looking to remove 3 cc's or better....the radiused chamber will give better quench.....
One thing i know about JE and Wiseco is that the CNC program they use for the dome is the same for any bore size....
A bigger bore will have more compression....soooo....relieve the chamber to go along with it.....
I bet if I went to a 12:1 piston with a massaged chamber and .430 webcam it would run just fine on 93 octane....

Jebby

Hey Jebby, I was just looking at my spare head & jug & WOW! There's really quite a distance between the cylinder wall & the outer edge of the chamber where the valve is most shrouded. I really don't know how that much material can be safely removed. I'd love to see a pic or hell, even a sketch of what you would like to accomplish.
 
Is it ok to mix race gas with regular gas?

I think you can buy race gas by the drum at some places lol.
 
Be carefull running a mix gass set up only mix what you need to fill the tank and shake the bike around really well like a 2 stroke so you don't get a lean spot as easy
 
Is it ok to mix race gas with regular gas?

I think you can buy race gas by the drum at some places lol.

People have been doin it for ages man. I can buy a 5gal can of VP 110 @ my local Yammy shop but it's like $55, not many options here otherwise. I certainly wish I could find some Cam2 locally.-- Weston, it's gonna be an experiment playing with that mix ratio so yeah, definitely gonna make sure I keep the mix "shook up"
 
Yeah there are racing sports in nearly every state, so I'm sure there is somewhere that sells it by the gallon.
 
yeah anywhere that has dirt track car races will have someone there selling fuel most likely. Or you can find out where everyone is getting their fuel.
 
Hey Jebby, I was just looking at my spare head & jug & WOW! There's really quite a distance between the cylinder wall & the outer edge of the chamber where the valve is most shrouded. I really don't know how that much material can be safely removed. I'd love to see a pic or hell, even a sketch of what you would like to accomplish.

Unfortunately I don't have this info yes as I yet to have a good spare head to play with......I have jumped back on my CBX bike project because
it cooled off a bit.....
When i know...everyone here will too......

Jebby
 
Now, if you could get a good build motor in this thing, it would be a ROCKET! Weights about 300lbs...
103_0185.jpg
 
Back
Top