stingray719
TY 4 Stroke God
Sad Pioneer is gone. 8FP can be had used on Ebay, Barn Of Parts (when in stock) and other places. Thunder Products for shims, multiple places for GWG spring if not your local Yamaha dealer.
rbell14
TY 4 Stroke Guru
Interested in the upgrade but have a few clarification points:
This COTC can be done with the 8DN or the 8JP belt right? ( I think many have used 8DN as a preference) what does 8DN deliver on its own on a stock machine?
Stage 1 shims - what do the shims actually do? (Further shift out) also is 4mm or 6 mm shim a preference or is a measurement required to determine which one? What does stage 1 by itself actually accomplish for my understanding.
Stage 2 - add green/ white/green spring and noted weights to the shim. Is this a common spring that bender racing carries.
Thank you for clarification to my questions.
This COTC can be done with the 8DN or the 8JP belt right? ( I think many have used 8DN as a preference) what does 8DN deliver on its own on a stock machine?
Stage 1 shims - what do the shims actually do? (Further shift out) also is 4mm or 6 mm shim a preference or is a measurement required to determine which one? What does stage 1 by itself actually accomplish for my understanding.
Stage 2 - add green/ white/green spring and noted weights to the shim. Is this a common spring that bender racing carries.
Thank you for clarification to my questions.
stingray719
TY 4 Stroke God
8JP belt really sucks and is twice the price of 8DN
Stage 1 will give you a good boost but go for stage 2 to get it right. 4mm for top speed, 6mm for mid range. The reason it works is the stock spring is so weak as compared to other Yamaha 4 strokes.
Stage 2 GWG spring is a Yamaha 4 stroke spring readily available most places. I prefer the "soft touch spring" from Barn Of Parts over the GWG though after much testing.
rbell14
TY 4 Stroke Guru
Thanks for the update. I get it now.
One last question, I can switch to 8DN now on my stock sled, with out any other adjusts other than checking belt deflection?
One last question, I can switch to 8DN now on my stock sled, with out any other adjusts other than checking belt deflection?
stingray719
TY 4 Stroke God
Correct, either add 3 washers one to each deflection bolt or buy the OSP deflection tool.
Dmarks
Veteran
- Joined
- Jan 9, 2014
- Messages
- 41
So for the stage two portion the spring from barn o parts is the only thing that should be done? Or is there weights or shim that must be done with this. Pardon my ignorance but IV tried to go over all pots on this and it is long
rbell14
TY 4 Stroke Guru
Stage 2 adds the GWG spring and the new weights that are noted in the first post. The shims will be needed unless you did the shims in stage 1 and added stage 2 later.
stingray719
TY 4 Stroke God
It has became confusing as the post morphs.
Stage 2
GWG primary spring (I ended up liking the Soft Touch Spring from barn of parts, seemed to have same finishing rate as GWG but very smooth take off)
8FP Yamaha weights used or new
3.6 gram rivets to go in above weights
4mm to 6mm primary spring shim (Thunder Products is fastest and easiest)
You can use 8JP stock belt but the 8DN is half the price and holds up better.
Stage 2
GWG primary spring (I ended up liking the Soft Touch Spring from barn of parts, seemed to have same finishing rate as GWG but very smooth take off)
8FP Yamaha weights used or new
3.6 gram rivets to go in above weights
4mm to 6mm primary spring shim (Thunder Products is fastest and easiest)
You can use 8JP stock belt but the 8DN is half the price and holds up better.
stingray719
TY 4 Stroke God
Parts are on the way, summer testing the same way the COTC was initially tested then actual snow testing late November.
THEN, testing with OSP weights on turbo.
As the weight profile is very much like the COTC I suspect I will have good news as the OSP is adjustable. But, as always I want to do good solid testing to prove it before I recommend anything.
Oh, just in case anybody asks I paid for the OSP weights so there is no conflict of interest in the final assessment.
THEN, testing with OSP weights on turbo.
As the weight profile is very much like the COTC I suspect I will have good news as the OSP is adjustable. But, as always I want to do good solid testing to prove it before I recommend anything.
Oh, just in case anybody asks I paid for the OSP weights so there is no conflict of interest in the final assessment.
Same here. I can't wait. Will post the final setup in the FAQ thread "Post your clutch setups" but anyway the magnets make it so easy to tune. Much faster than anything else. The extra cost vs stock 8fp is not even a factor when you consider the time saved tuning.
stingray719
TY 4 Stroke God
Agreed. At 279 bucks for weights AND gwg spring it is still kinda cheap.
stingray719
TY 4 Stroke God
Weights are in, comparison pics below.
8GL with bump ground off heel on top of OSP below
OSP on top of stock 8FP below
8GL with bump ground off heel on top of OSP below
OSP on top of stock 8FP below
stingray719
TY 4 Stroke God
OSP on first look does have a steeper ramp than 8FP but the OSP weight body is different so in my opinion it is going to take real world testing to see how much difference there is.
Here is D&D/Magnaforce vs OSP
This is great post Stingray. If anyone else has other comparisons that they have run in Viper please add them. We can sticky this.
