scott32
TY 4 Stroke Guru
- Joined
- Jan 12, 2009
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- Location
- huron county, ontario
- Country
- Canada
- Snowmobile
- 07 Apex RTX se, 09 Nytro XTX
Studroes, keep us updated on your progress. Please put the zero miles 127hp sled back on the dyno after 100 miles. You are comparing two different motors that may never be the same. You have developed a theory. Theoretically, if your motor started at 127hp and ends up at 140hp after break-in period than it is possible your theory may be correct. But after many years of comparing sled to sled there are good ones and there are bad ones. I've heard of a few Vipers that are over-reving before break-in, guys are adding weight to the primarys to pull rpm down off the rev limiter. Is it that Cats electronics are all over the place, I dunno? What I do know though, is that you cannot dyno two different motors and use that as a baseline to go off of. Keep the research going, Cheers.
shadow44
TY 4 Stroke God
Studroes144 said:
No, my sled made 139.9 hp with 2300 miles on it....a few months later it made 127.9 on a different dyno. if you think a 4 stroke will make 10-15 hp after it's broke in then I guess the 06 to 10 Apex is more like 165 hp...and the 11 and up Apex it closer to 175...
Your sled at 100 miles is probably broken in....it doesn't take 1000 miles to break in a motor lol, heck, Hindle breaks in bikes on the dyno...you don't think he puts 1000 miles on them do you?
Yamacat21
TY 4 Stroke Junkie
In theory, I have $1500 burning a hole in my pocket! What's the best bang for my buck, oh buy the way I need to be able to run 87 octane because a lot of places I go you can't get 91.
shadow44
TY 4 Stroke God
I would be going for the full HINDLE exhaust and a clutch kit.
Superfletch
Veteran
^ +1. Full Hindle header, airbox mod, PCV, and clutch kit. Probably just about your budget and should see 15 reliable pump gas hp. I will update in a week or so with back to back dyno results on these mods. All from Hurricane Perf!
scott32
TY 4 Stroke Guru
- Joined
- Jan 12, 2009
- Messages
- 758
- Reaction score
- 37
- Points
- 368
- Location
- huron county, ontario
- Country
- Canada
- Snowmobile
- 07 Apex RTX se, 09 Nytro XTX
Then open her lungs and put it to the groundYamacat21 said:
stingray719
TY 4 Stroke God
shaddow44 said:Studroes144 said:
No, my sled made 139.9 hp with 2300 miles on it....a few months later it made 127.9 on a different dyno. if you think a 4 stroke will make 10-15 hp after it's broke in then I guess the 06 to 10 Apex is more like 165 hp...and the 11 and up Apex it closer to 175...
Back in my racing days we built motors with more clearance so long break in was not required. I suspect Hindle does the same. Yamaha however builds them tight and you do get ALOT of friction and power loss in the first 200 to 300 miles especially in the first 50. This is not an opinion, this is fact coming from someone who has built and rebuilt many many Yamaha engines. New engine with close tolerance and aggressive cross hatch hone in cylinder creates friction and heat no way around that.
As a side note I built a racing engine for Hunters cross country racing team decades ago and we polished all the moving parts we could with Jewlers Rouge and fine finished the cylinders by putting pistons on an old rod and running them in with jewlers rouge. (run piston up and down by hand for 15 minutes clean all parts and repeat) Took forever it seemed but NO break in and engine pulled over like one spark plug was out. Sorry, got offtopic.
