high rpms at 55 and above

[BartBuddy28]

Does 4,000-4,500 rpm at 55 mph sound right? I feel like my xs is screaming and wanting a sixth gear, is there somethong to adjust?

 

[Coleman67]

I feel like my bikes "sweet spot" is right in that range and it doesn't seem like it's screaming -- but I have owned various inline four's in the past. That RPM range puts my speed around 60 to 65 MPH with stock gearing. Are you running stock sprockets? There is a lot of information on here about changing sprockets. A search will produce several threads.

 

[Scrambled]

At 55 mph you should be around 3500- under 4 grand anyway . Like Coleman said ,it may be gearing ( I run stock 17 / 34 sprockets on mine ) or maybe your clutch is slipping a bit . What happens when you hit the throttle hard in 5th gear at 4500 rpm ? Does it take off ,or do the revs climb and your speed doesn't increase much ?

 

[pamcopete]

Here is a Excel spreadsheet that shows RPM vs MPH for all combinations of gears, sprockets and wheels.

RPM vs MPH

 

[BartBuddy28]

Sprockets are stock, replaced them during winter 17/34 is what was on it, and thats what i replaced with

 

[BartBuddy28]

Looking at the chart pamcopete gave me, it wouls seem i need a 33 tooth gear and not a 34, i did purchase a 32 tooth wonder if that will help. I used it before after installing a 4 gal tank to replacr the original stock 3 gal. While using the 32 gear, my tank would only get 180 miles out of it, which is what i got whwn i had a stock 34 sprocket and a 3 gal tank....common math says that a 4 gal tank with 34 tooth should give me 240 miles...but even before the rear gear swap out, orignal gears, i remember the bike running around 3500 at 55..... I have done a lot of electrical work to this bike in the last five or six months...so im really lost.. clutch noes not feel like its slipping at all in fact i think its working perfectly. I do notice a weird rpm change from 2nd and 3rd gear, like there is no change in rpm really...im prolly losing you by now but basically i just think somethings off or needs adjustment

 

[tonyc]

If you are stock your clutch may be slipping.

 

[scabber]

The speedometer could be off.

 

[DIRTY DOG]

I run 17-31 love it still has power and less vib at freeway speeds

 

[jd750ace]

My speedometer is significantly off according to my gps.