2004 r1100s stutter on accel

[SANTA]

So i have now seen this on 2 different r1100s.  when you roll the throttle in neutral it spins up fine, but when you let the clutch out in first it stutters a bit and then smooths right out, the first bike was mild, this second one is rough.

history for second bike: new plugs, stick coils, air filter, fuel filter, cleaned throttle bodies (did not touch tps or stop screws), checked valves, bike has 70oookm  and had a clutch and input shaft done about 30k km ago.

 

 

 

 

[Lowndes]

That might be your clutch slipping (best case) or it could be the dreaded spline failure on the trans input shaft.  The splines usually just let go and the clutch will do this for a while.  

 

Check the hydraulic reservoir for the clutch.  If it is low, you might have had the slave cyl failure that dumps the hyd fluid (DOT4) out of the slave cyl where it travels down the clutch pushrod to the clutch and destroys the friction plate.  Look for traces of "oil" on the bell housing/engine seam, both sides and bottom.  That is the tell tale.  AMHIK.

 

Sounds like you need a new clutch, tho.  And install a weep hole in the slave cyl housing while you're in there.  Don't want to do this again.

 

You can visually check the splines thru the starter hole.  Remove the starter motor (two bolts and two wires) and shine a light into the splined shaft where it goes into the friction plate F-spline.  "Rock" the clutch both way with the rear wheel, or with fingers thru the starter hole and see how much play there is in the splines.

 

Post back with pics, show us what you find!!

 

Starter hole (rear half of bike removed for clarity):

 

All the pics from my '99 R1100S clutch and slave cyl replacement: https://photos.app.goo.gl/Pj7KoLVP8C1Nb6RU6 and https://goo.gl/photos/QEN3xyQVWXW1jraT6

 

My old K1200 bell housing - "oil" from slave cyl:

[dirtrider]

8 hours ago, SANTA said:

So i have now seen this on 2 different r1100s.  when you roll the throttle in neutral it spins up fine, but when you let the clutch out in first it stutters a bit and then smooths right out, the first bike was mild, this second one is rough.

history for second bike: new plugs, stick coils, air filter, fuel filter, cleaned throttle bodies (did not touch tps or stop screws), checked valves, bike has 70oookm  and had a clutch and input shaft done about 30k km ago.

 

 

 

 

Morning SANTA

 

First thing to try is a TPS re-learn, if that doesn't help then you need to look into other areas. 

 

Does it still have a stock exhaust system? If it has an aftermarket exhaust that is open (no real baffles) then you can get some exhaust reversion at light throttle-up. This is difficult to cure or help without adding a lot of fuel at light throttle-up or re-working the exhaust to stop the reversion pulse. 

 

Otherwise, you need to go over everything like coil voltage (later twin spark engine bikes added a 2nd load relief relay to increase voltage to the stick coils).

 

Try disconnecting the o2 sensor then ride it to see if that changes anything, might point a finger at that area.

 

Check your fuel pressure, throttle body balance & cable adjustment (if the R/H side throttle plate opens before the L/H side it takes a gulp of air on that side before the fueling catches up as the L/H side has the TPS on it.

 

Make sure you have the correct CCP installed (at least until you verify that the CCP isn't the problem)

 

Without actually riding the motorcycle all you get is a lot of guesses.

 

You are probably fighting an exhaust reversion issue (non stock exhaust),  or a spark issue, or a light throttle fueling issue, or possibly even a leaking intake valve issue.  

 

Probably wouldn't hurt to check the TPS voltage at (choke off) closed throttle, should be around .365v then smoothly scroll to 5 volts at about 1/2 throttle.

 

Maybe measure the supply voltage to the stick coils & the fuel injectors with at engine running at idle.

 

We can't see it, feel it, or ride it over the internet so you do need to first determine if it is engine related or more drivetrain related  like clutch or splines as Lowndes mentioned above.