Clutch, transmission, Final Drive or electronics.... Thoughts anyone?

acara1796

acara1796

AHRMA Racer, Advanced MC Instructor
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Joined
Sep 21, 2006
Messages
77
Location
Campton Hills, IL
Bike
07 ST1300
Forgive me if this symptom has been posted before but my search terms didn't find anything that match the issue. Probably not using the right terms :/

06 ST1300

Coming home from work this afternoon I took off from the light and rev'd above 4000rpm, shifted to second and the engine rev'd to 6 or 7, had no additional drive. I backed off the throttle and drive returned at or below 4000rpm. Now, I thought I just horribly botched the shift. Except as I continued down the road, the problem became overly apparent in every gear. Engine rev's high and no power to the drive if I throttle up above 4000rpm. This happens staying in any gear and trying to rev higher then 4000rpm. Best speed I can achieve in any higher gear is about 45mph. Under load the transmission seems to shift properly.

I just did a full fluid change at the end of February. Included, the clutch bleed. Not sure if it is the clutch slipping - plates, trans (I really hope not) or sensor perhaps.

Any ideas are more then welcome.

...Kim
 
Kim, sorry to say it sounds like the clutch...The fluid change would have been my 1st shot at fixing it.
 
I have a couple questions...first, what type of engine oil do you use? and what type of fluid did you use when you bled the clutch?
First thing I'd do is change the engine oil, I'd recommend HDEO like Valvoline Premium Blue or Delo 400, this will clean the engine and clutch plates better than most motorcycle oils, next, I'd open the clutch mastercylinder, remove the diaphram and make sure you didn't bend the "protector" (little spoon like thing in the center of housing)
If you obstruct the return opening, it may cause problems, After doing that, flush & bleed the clutch again, until you have 2 or 3 cylinders full through it, and the fluid is nice and clear.
I'm thinking if it was ok before you bled the clutch, you either misplaced the protector, or left air in your system.
After bleeding the clutch, strap the lever open for a couple hours, or overnight to let any residual air out.
Oh yeah, don't use a vaccume pump, do it manually or use a motion pro bleeder or similar tool.
Let us know what happens.
Igofar

After looking at your photo's, now I'm wondering if Mellow is right and you just toasted your clutch plates LOL
Nice albums...
I'd still do the work above just to make sure...
.02
 
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The odd thing is if it is a slipping clutch they usually don't go all at once and even when they begin to go south they will grab and work OK in the lower 3 or 4 gears. Only in the higher ratios of 5th or 6th (if a bike with six speeds) will it begin to slip. If it worked OK going to work this morning it's not likely the clutch gave it up while sitting in the parking lot. I suppose anything is possible though and perhaps a part failed in the clutch basket/clutch plates that does not allow the clutch to fully engage when the clutch lever is let out. That would explain a sudden failure.

If it was air, moisture, or restricted passages in the hydraulic system the clutch would not DISENGAGE. The lever would be spongy or have no resistance. The problem you describe is the clutch will not ENGAGE or hook up allowing the engine to drive the rear wheel through the transmission.

Are you saying that the engine revs over 4000 rpm but the bike will not exceed 45 mph? Does the clutch hook up in second or third gear and allow revs greater than 4000 rpm and engine revs to match road speed or does the bike stop accelerating at 45 mph and the revs just increase as throttle is increased no matter what gear?
 
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Mellow said:
Kim, sorry to say it sounds like the clutch...The fluid change would have been my 1st shot at fixing it.
Click to expand...

Further static test tells me it is the clutch. I pulled the lever and secured it. Shifting through the gears and trying to move the wheel. In first, it was tough to turn the wheel. Was not moving like it should. Moving through the rest there was not as much resistance but tough to get it to run through them. Compared it to the 07, which was more fluid. Of course the 07 is a year newer and half the mileage. It doesn't get run as hard either. :)



Igofar said:
I have a couple questions...first, what type of engine oil do you use? and what type of fluid did you use when you bled the clutch?
First thing I'd do is change the engine oil, I'd recommend HDEO like Valvoline Premium Blue or Delo 400, this will clean the engine and clutch plates better than most motorcycle oils, next, I'd open the clutch mastercylinder, remove the diaphram and make sure you didn't bend the "protector" (little spoon like thing in the center of housing)
If you obstruct the return opening, it may cause problems, After doing that, flush & bleed the clutch again, until you have 2 or 3 cylinders full through it, and the fluid is nice and clear.
I'm thinking if it was ok before you bled the clutch, you either misplaced the protector, or left air in your system.
After bleeding the clutch, strap the lever open for a couple hours, or overnight to let any residual air out.
Oh yeah, don't use a vaccume pump, do it manually or use a motion pro bleeder or similar tool.
Let us know what happens.
Igofar

After looking at your photo's, now I'm wondering if Mellow is right and you just toasted your clutch plates LOL
Nice albums...
I'd still do the work above just to make sure...
.02
Click to expand...

Engine oil - Repsol synthetic blend 10w40 4T
Fluid was NAPA DOT4 (not the greatest but they have big bottles and I have lots of motors to maintain)

Clutch lever is not spongy and has the resistance I would normally expect.

I have been riding this one all through the month of April on those fluid changes. Moonshine, daily commute, a 200 mile day ride last Sunday, teaching etc.

thx on the albums. :)

The fluids are going to get changed I suspect no matter what :/

dduelin said:
The odd thing is if it is a slipping clutch they usually don't go all at once and even when they begin to go south they will grab and work OK in the lower 3 or 4 gears. Only in the higher ratios of 5th or 6th (if a bike with six speeds) will it begin to slip. If it worked OK going to work this morning it's not likely the clutch gave it up while sitting in the parking lot. I suppose anything is possible though and perhaps a part failed in the clutch basket/clutch plates that does not allow the clutch to fully engage when the clutch lever is let out. That would explain a sudden failure.

If it was air, moisture, or restricted passages in the hydraulic system the clutch would not DISENGAGE. The lever would be spongy or have no resistance. The problem you describe is the clutch will not ENGAGE or hook up allowing the engine to drive the rear wheel through the transmission.

Are you saying that the engine revs over 4000 rpm but the bike will not exceed 45 mph? Does the clutch hook up in second or third gear and allow revs greater than 4000 rpm and engine revs to match road speed or does the bike stop accelerating at 45 mph and the revs just increase as throttle is increased no matter what gear?
Click to expand...

Revs higher then 4000 in any gear doesn't match road speed or increase it. Your 2nd question is yes. I do think it is actually dropping road speed

When I throttle up over 4000 rpm the rear wheel stops driving. In gears 3 and up 45 is the best speed at 4000 rpm. Over the 4000 mark in all gears it reacts almost like I have pulled in the lever (disengaging). To be certain I would need to ride it again to see if I have a road speed drop off. I believe it did. I also notice a pulse/surge on a sustained 4000 rpm (like it wanted to drive more)

Thanks guys, really appreciate the help.

Wouldn't you know I have Stay'n Safe Tours I have to run next week. May be using the hubby's 07.
 
Just curious what's the mileage? Do you do a lot of parking lot courses or mostly track days?
 
Well, that does sound like the clutch is slipping. The oil is non moly MA rated which is good. Perhaps the slave cylinder is binding and not allowing the clutch to fully engage. I'll be interested in the fault when it is diagnosed.
 
What kind of clutch lever do you have on the bike? I've seen some of the small or short levers have fitment issues? Just guessing.
Let us know what you find.
 
Mellow said:
Just curious what's the mileage? Do you do a lot of parking lot courses or mostly track days?
Click to expand...

Believe it or not the mileage is low. The 06 just turned 30,000 on Monday actually. My commute is 4 miles one way and we don't get to tour at the moment.

Haven't had either ST on a track. Do ever really plan to. Plastic too expensive to replace.

Mostly use the ST when teaching Total Control Advance Riding Clinics, Stay'in Safe and one we call Motorcycle Control Clinic. Total Control does not use the clutch at all except to get moving. Now I just started teaching the MCC and it is real world slow speed maneuvering techniques. So guess what is used in the friction zone. I believe while becoming efficient in these techniques I have burnt the clutch.

I be looking at using one my others to teach MCC. One that has a clutch that I can replace without having to drop the engine.
 
dduelin said:
Well, that does sound like the clutch is slipping. The oil is non moly MA rated which is good. Perhaps the slave cylinder is binding and not allowing the clutch to fully engage. I'll be interested in the fault when it is diagnosed.
Click to expand...

Igofar said:
What kind of clutch lever do you have on the bike? I've seen some of the small or short levers have fitment issues? Just guessing.
Let us know what you find.
Click to expand...

Lever is stock. Found no need to change it, really.

I think I have burnt the plates. May drain right away and see if there are pieces of plates floating around. I'll be sure to keep everyone up to date.

Has anyone change their clutch plates and does the engine really have to be dropped?
 
If going in to do a clutch job you may want to consider a water pump as well. You have basically pull the water pump to get to the clutch basket.

Personally I would say clutch issue. When you changed fluids are you using a different oil than you have in the past? Or was it a change with the same oil you have always used?
 
sennister said:
If going in to do a clutch job you may want to consider a water pump as well. You have basically pull the water pump to get to the clutch basket.

Personally I would say clutch issue. When you changed fluids are you using a different oil than you have in the past? Or was it a change with the same oil you have always used?
Click to expand...

Same I have been using for 4 or 5 years now.
 
Confirmed the clutch. Smoked, Fried, toasted... etc Really surprised I made it home when it finally really let me know there was a problem. Put an Aftermarket Clutch and springs in. I am obviously hard on it. :rolleyes:
06stclutch3.jpg 06stclutch1.jpg
 
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