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bombsquad54 · #31 Post by **bombsquad54** » Tue Dec 14, 2004 8:49 pm

with the moto map, the motor revs too high, causes valves to float, and bearings to burn up. turn it down to 10,500. to be safe.

jacobw · #32 Post by **jacobw** » Tue Dec 14, 2004 8:52 pm

hey bomb I race xc and rarely ever get a chance to even get close to the 10,600 rev limiter on my cannibal so I think I am safe I just need to do the stage 8 this winter:(

Derno24 · #33 Post by **Derno24** » Tue Dec 14, 2004 9:07 pm

[QUOTE]Originally posted by bombsquad54
with the moto map, the motor revs too high, causes valves to float, and bearings to burn up. turn it down to 10,500. to be safe. [/QUOTE

I know you are trying here, but a moto map has a rev limiter of 11,600 stock cannibal is 10,600. Valves aren't floating with a moto map. What Jeff is talking about is the XMX or one of the many other maps out there that were made to push the motor to the limits.

USAMoto00 · #34 Post by **USAMoto00** » Tue Dec 14, 2004 9:19 pm

I think it has to do with HOW the quad is ridden too. Some people use the motor and rev limiter to there full potential. Others like to go by the sound and feel of the motor and although they might "lose" a little power by shifting prematurely, they prolong the overall engine life as Jeff and Derno were suggesting. I guess it depends how often you like to work on your quad and how much horsepower you want out of it. Everyone rides for different reasons and wants something different from their quad. To each his own, truely fits here. Just remember, all full out race machines require more maintenance than your occasional trail machine.:deal:

bombsquad54 · #35 Post by **bombsquad54** » Tue Dec 14, 2004 9:19 pm

well at the limiter the valves do float. thats what happens to all race motors, honda- yamaha- suzuki. when they drop valves. 10,600 should be just fine. you can push the motor hard without going up to 11,600. all other race quads run around 10,500 to 10,800.00 11000+ is too hard on them. i ride in the rev limiter so i wont know the differnce, we will see how my motor holds up with the 10,600.00. 400ex's dont hardly ever drop valves because even with a rev box they are only at low 10's. thats just what i think, derno, thats just what i think, im not argueing. it just makes perfect sense

theJeStEr1340 · #36 Post by **theJeStEr1340** » Tue Dec 14, 2004 10:17 pm

QUOTE

Originally posted by bombsquad54
well at the limiter the valves do float. thats what happens to all race motors, honda- yamaha- suzuki. when they drop valves. 10,600 should be just fine. you can push the motor hard without going up to 11,600. all other race quads run around 10,500 to 10,800.00 11000+ is too hard on them. i ride in the rev limiter so i wont know the differnce, we will see how my motor holds up with the 10,600.00. 400ex's dont hardly ever drop valves because even with a rev box they are only at low 10's. thats just what i think, derno, thats just what i think, im not argueing. it just makes perfect sense

400ex's don't make power as high as out dales do either. That is one thing I noticed about these things that I love. This bike will yank your arms untill it hits the rev limiter, in every gear... well I dunno about 5th really, never gone that fast.

wanablaze · #37 Post by **wanablaze** » Wed Dec 15, 2004 2:29 am

400ex's are OHV motors, cam in block. I'd never expect them to rev to 10k rpm.

haydug · #38 Post by **haydug** » Wed Dec 15, 2004 2:35 am

I tried racing a 400ex 2 years ago. After destroying every part of the motor at one point or another, I gave up. The last straw: running 7th in pro-production at High Point, and dropped a valve! :cry:

cannondale27 · #39 Post by **cannondale27** » Wed Dec 15, 2004 12:55 pm

Our motors definitly will drop valves and it does seem to happen no matter what rev limit you are running.That said I am going to be running maps with 10,500 limit or lower just to be safe.With all the mods done the lowend is way improved so I feel I can make up the rpm loss with higher gearing.You guys with stroker cranks should easily be able to do the same thing.It would be nice to have a map select for those special occasions though.

Timbomoose shaved crank,seperate pin,z400 bearing,Timbo rod run for first 20hrs with Zack1 map 11,800 rev limit.Now running Moto 10500 limit when ported head comes back.Crank still great piston/Iron sleeve was wore.Trying the new JE piston and sleeve from Haydug.

Derno24 · #40 Post by **Derno24** » Wed Dec 15, 2004 2:20 pm

So if it happens no matter what rev limit you run then why switch? We have come so far to let the one thing that seperates this quad from others be a limiting factor. What would be the solution? Stiffer springs? Better Valves?