I have been having intermittent problems with my K1200LT slipping under heavy throttle when starting out in 1st gear. Bike starts to move and then lets go. It acts as if the clutch lets loose. No slippage in higher gears. If I pull in the clutch and let the engine go back to idle and ease on the throttle, works fine.

Normal clutch problems slip in higher gears.

Weep hole drilled, no oil.

I am leaning towards a drive shaft problem (rubber slipping?) however I would think that once it broke loose, it would not hook up again.

Thoughts?

That is an odd one Pace. You say in first gear under heavy throttle. Make sure your clutch is fully engaged before hammering the throttle. I suspect that if you exceed 1,500 RPM before the clutch is fully engaged you may heat it up to a point it will begin slipping under heavy throttle. Try a few gentle launches where you keep it no higher than 1,200 until you can remove your hand from the clutch, then try to hammer it and see if she slips.

The typical drive shaft failure is it melts and grabs again but that does not last for very long before it just flat slips forever.

Got her all torn down today...



It appears to be the drive shaft.... Sure is easier changing out the drive shaft instead of the clutch!

This photo is looking into the rear wheel fork from the rear.
The area circled in red is evedince of rubber slinging off the drive shaft. That areas is right where the end of the forward section of the drive shaft which contains the rubber.



This photo shows where the rubber has moved at some point.



I guess it breaks free and the friction from the slipping allows it to bond again once it stops spinning and has a chance to cool a bit.

I think I have another drive shaft so I'll give it a try. Otherwise, I guess I'll be looking for one.

I'll let ya'll know how it turns out.

BTW, I am taking tons of pics of the whole tear down process. Fixing several things. I'll put together some tutorials when I get her finished.

WOW!, in a short time, you tore into that with confidence and figured out the problem. From what I can see and from what I've learned here this is a rare issue. Glad you solved it.

I have torn this bike down numerous times. It gets easier each time I do it. Tearing it down to the level in the previous picture took about 5 hours. Helps to have the right tools.

I was hoping you we're doing more than just the shaft when I saw how far you took her down. Good to know it was the shaft rubber.

I hope you are correct. That sure looks like spline lube to me, but can't see what it lines up with in the photo. Nice lift, by the way.

Quick question about your lift table. I notice it is wide enough for a Quad. Do you find it is too wide to reach and work on the bike comfortably? I've thought about putting wings on my lift.

Thanks

I have the same type of lift and those wings pull off. Look at the side and you will see the lock pins that hold them on tubing that also pulls out.

My lift is a HANDY lift. Very strong and stable.

The table has removable wings on it. I find that for most things, the wings stay on as they provide extra space for tools and parts. Another plus for the wings is they provide a wider platform to put your feed down when riding the bike up on the lift.

Spline lube is further towards the rear of the tube as shown in this photo.



I have an extra drive shaft I am going to install. I'll let you know how it turns out.

Here is a list of the things I am doing on this round. May not do all of them now but this is the list.

Repairs:
Replace busted rear brake line (between master cylinder and steel tube leading to ABS)
I was able to get one made locally with SS braided line. More on this in another post
Repair slipping clutch/drive shaft (turns out it is the drive shaft)
Replace Throttle cables with new style cables
Synching throttle bodies
Check/adjust TPS
Check/adjust Throttle Actuator
Check/adjust Hall Sensor

Appearance changes:
Clean and seal (anodize or zinc) bolts. Replace any damaged bolts.
Powder coat brake calipers
Powder coat rear drive/swing arm
Powder coat wheels (may anodize them)
Power coat front forks. (may anodize them)
Install high beam HID
Carbon fiber all chrome
Carbon fiber instrument cover under wind shield
Carbon fiber black parts of sting ray
Carbon fiber handle bar covers
Recover knee pads, speaker covers

Here is a picture of the parts taken off so far. All cleaned up and ready to reinstall or do further work (powder coat/anodize)



My son and I are taking numerous photos and videos. I'll be producing some tutorials about how to do most of the things I am doing. Still trying to decide wether to do instructables, PDFs or videos.

Thoughts?

Interest?

I love the lay out of parts. Reminds me of the old aircraft photos that showed all the weapons that the plane could carry laid out in front. Enjoy your wrenching!

That is a lot of work, and the way you laid it out and documented it is impressive. I had mine apart that much and more, but never had the patience to document it like that. Always was in a hurry to get it on the road again.

Just in case you do not know, you mentioned re-coating the bolts, anodize or zinc. I am not aware of anodizing steel being done, only aluminum, magnesium, titanium, and zinc. the bolts are steel. One thing to be very careful of is to be sure if you have anyone plate them, try to get it electroless. Electroless nickle could be a good choice, but would require stripping the current coating down to bare steel. If they to use an electrolytic process, be absolutely sure they know how to avoid hydrogen embrittlement! That is sometimes a result of improperly done electrolytic plating, without the proper post baking. That can cause heads to snap off fasteners, particularly higher strength steels.

http://corrosion-doctors.org/Forms-H...rittlement.htm

Very interesting find with the two piece drive shaft slipping.

My LT has the same symptoms. Only slips occasionally when starting out fast in first gear. She never slips in the upper gears.

I'm wondering if it's just my drive shaft. I have no other indications of fluid leaks anywhere.

Thanks for posting this info. I must admit that it is hard to understand why the "rubber" would only slip occasionally and not all the time.

The rubber breaks free under sudden extreme torque. Once free, the friction from slipping heats the rubber. When you release the throttle, the rubber sticks again, although not as good as new.

That's whe it's intermittent and only happens at sudden hard starts.

Man, you are lucky to have all that room and a lift. I replaced my clutch in the back yard on a piece of plywood..................