Lost 500 RPM'S Any Ideas?

[pdrmike]

Went riding this week with 3 RX 1's, my buddies 04 ran 10500 always without skipping a beat, half way through the trip it starts running 9700 and makes it's way to 10000. It has ECP with evac and stock clutching. Filters appear to be clean, we changed plugs and belt with no change. Any ideas, thanks, Mike

 

[boat.man]

bad gas? some of those resorts have kinda old gas in the tanks
mine will pull a few more rpm's on 87 octane vs 92

 

[RX1-er-2005]

I've had a simular situation caused by "GAS" if you run premium in RX's you tend to lose rpm's, premium needs more heat and compression to egnite pending on weather and atmosphere on different days...anyways I don't want to get to scientific here but try running REGULAR 87 octane as much as you can.

my .02

 

[black john]

500 rpm

one bad coil will di that . try cleaning you coil,s inside and out with braek clean. and just for gigel,s do it over a clean white cloth you will be suprized how much carbon you will see.

 

[pdrmike]

We were running 92 not 87 octane. It's worth a shot going back to 87. Thanks for the ideas so far. Mike

 

[suprfst]

One more thing to check is primary spring It couldve taken a set.Usually the fade gradully over time but ive seen them break as well on other sleds.Check secondary spring as well they can break too.

 

[pat the rat]

same thing happened to me,couldnt get the rpm's above 9500,changed the primary spring to a or silv or and made all the difference,now im seeing 10 500 easy,even a bit more but you dont want to go much more than 10 200-10 400,my cam was real thight prior to changing the spring so i'll loosen it to see if i can drop about 200 rpm

 

[Bop]

I only get 9500 on my 03 RX1. I ordered an orange-silver-orange spring today. It will be interesting to see what diff it makes exactly. I'll post on Weds after it's installed.

 

[pdrmike]

I know i can change the clutching to get more rpm's, we want to know why we lost it in the first place. Thanks again for the help, Mike

 

[grader]

dirty coils can cost some rpm loss. remove rubber and clean. center to center change from motor shifting can also lose rpm. dirty filter in air box can also lose rpm, (beltdust). one bad plug can also cause this problem. check these areas and see if you get the rpm back.

 

[Smokey]

I had the same problem tried everything. Turned out to be secondary bushings. I lost 1000 RPM. One bushing was badly worn didn't do the trick. Changed the other and it was back.

 

[Smokey]

Try this link regarding my problems.
http://www.ty4stroke.com/viewtopic.php? ... highlight=