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Discussion Starter · #1 · (Edited)
When I got my Vulcan restoration project started last year it had 10,700 miles on the rear tire, and plenty of tread. 3,800 miles later it’s done. I ride hard and spirited and on the twisty Santa Cruz road.
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I really was surprised by how grippy and responsive the stock Bridgestone Exedra was, and I enjoyed the stability of the wide flat tread. So I replaced it with the new upgraded Exedra G702.
Two things to note
  • The new tire has a fully rounded tread profile making it even more responsive and grippy at more aggressive lean angles. The stability is only slightly down and is very satisfactory.
  • The G702 construction causes a major change in tire pressure. At max load of 800 lbs it takes 41psi vs 32 for the OEM. For my weight of 175lbs riding one-up a base pressure of 36psi is recommended by the dealer. I actually drop that to 34-35psi to get a little more rubber on the road, preferring grip over mileage.

On to the splines. They looked just fine. Still had grease evident, no dust, and no spline chipping. Could see some spline distortion from the torque but that’s normal after 10,000 mi.

The high-percentage Moly is extremely hard to find and expensive. I used Lucas assembly lube I picked up at Autozone.
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Cleaned out the old grease with ChemTool careful not to spray on rubber seals. Applied a few teaspoons of lube and a finger coat of red bearing grease on the rear splines. Here is the before photo.

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On the front driveshaft I pulled the shaft forward out of the coupling, then pulled the rubber boot back to expose the splines, and squirted the lube onto them, using a flat blade screwdriver to rotate the shaft until fully covered. Applied a final coat of wheel grease (I’m usually guilty of a little overkill) and cleaned up any excess that dropped down before pressing it all back together. Here is the before photo. Notice how dry it is but in perfect shape because it doesnt get the up/down movement the rear splines get from swing arm movement.
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Final note: service manual says to use motor oil on the final drive gear teeth in the wheel, if my memory is accurate, but of course I did my slight overkill by doing that and adding a bit of Lucas MDS and wheel grease. I used it sparingly and wiped off excess, otherwise it will spin off and out and mess up the rear wheel. Don’t want this flung out and getting on the tire.

EDIT: Acadia pointed out that my memory was not accurate. Just use a light coating of high temp grease / moly on the gear teeth.

Buttoned it back up and it spins sweetly. I did hit the rear axle with 2500 smoothing sandpaper and a light coat of wheel grease.

Thanks for viewing. Comments welcomed. (especially about using the Lucas Assembly Lube MDS and adding a finger coating of high-temperature wheel grease. )
 

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I believe there's a reason high moly grease is specified. Replacement shafts aren't cheap.
 

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You're not the first, and probably not the last, to assume that.
 

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Thanks for viewing. Comments welcomed. (especially about using the Lucas Assembly Lube MDS and adding a finger coating of high-temperature wheel grease. )
Thanks for the nice pics. Having just done my first spline lube this weekend, and read the original lengthy thread from years ago - now sans pictures - I can appreciate what these pictures are showing.
FWIW, I'm not sure the manual says anything about "motor oil" on the rear wheel splines, though you've got me curious. Just checked the PDF version uploaded here as well as my Clymer's.
I was initially concerned about the black stuff flinging out of my rear hub. Turns out, the PO must've gone a bit heavy with whatever grease he used. Plus, it's been hot as blazes around here lately. So when I was checking my rear brakes, I did the complete spline maintenance at the same time. A little daunting at first but the worst part, I have to say, was trying to find this ultra special high-Moly grease everyone here talks about. I live in a big town and spent most of a day going everywhere to find anything close, including places that at least claimed to have the Loctite version - only to discover that they didn't. None of the bike dealers had - or used - anything like it either. They use - and I quote - "just plain grease on all of our final drives".
Not that it surprises me that dealers are prone to doing shoddy work. And not that I'm doubting the wisdom here in recommending high-Moly grease for this application. My only point is to say that it was by far the biggest hassle in this procedure.
 

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My Honda dealer acted like they never heard of the moly paste. Ebay had some way back then, but I like dirtrack's Belray lube.

I'll confess, I used a high moly wheel bearing grease. We'll see when I get a back tire, no rides until that happens, got a spot with cords showing, from that time I slid around a deer.
 

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I'll confess, I used a high moly wheel bearing grease. We'll see when I get a back tire, no rides until that happens, got a spot with cords showing, from that time I slid around a deer.
Whoa, that sounds like quite a scare! Did you dump it? Was it a night ride?

At least yours HAD moly in it. At the risk of earning everyone's scorn, here's what I ended up with. Mind you, and like I said, I'd had enough shopping for one day. Hindsight lesson learned: shop online BEFORE undertaking this spline procedure.
RED GREASE – Blastercorp
From the SDS, I'm disappointed to see that it contains zero moly but hey, at the end of my day, it was either this stuff which at least had a temp threshold of 550 degrees or some molyEP that I use on my backhoe which makes no such claims.
 

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2001 Kawasaki Vulcan 750
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Discussion Starter · #10 · (Edited)
I believe there's a reason high moly grease is specified. Replacement shafts aren't cheap.
Let's be clear. High moly grease is not called for.
What is called for is "high temperature grease" per the engineers who wrote the Kawasaki Service Manual.

Organism Font Circle Line art Auto part


Using Molybdenum disulfide lube arose from persons who had experience with automotive/other driveshaft applications, and Honda.

The Kawasaki service manual that is online is from 2004. Yes, there have been improvements in lubrication/protection for high torque applications since then.

MDS grease is excellent for driveshaft splines, and can be used to replace grease. But high temperature grease will work just fine. Kawasaki calls for the first application at 10,000 miles and then at 30,000 miles.
Font Material property Rectangle Parallel Pattern

I used Lucas Assembly Lube which is a low-percentage MDS. Exactly what percentage I could not locate. This I applied to the drive splines. Then, exactly as specified in the service manual, I used a few teaspoons of high quality high temperature grease in the coupling.

My driveshaft was in excellent shape when I did the maintenance. It has now been properly lubricated above and beyond what is necessary per Kawasaki. When I hit 30,000 miles, I will do the maintenance again.

I am absolutely positive this driveshaft and every well engineered driveshaft, which the 2001 Vulcan definitely is, that is properly maintained and does not undergo unusual climate / salt water / abuse will last a lifetime.

Flite you made an incorrect statement about high moly being called for. Don't rain on the parade for those who use proper lubrication as called for by Kawasaki engineers, and don't put unnecessary paranoia on anyone about driveshaft failures. Low moly, high moly, or high temperature grease will all work just fine. Your opinion is respected, but it is an option, not a requirement for satisfactory maintenance of the driveshaft.
 

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Whoa, that sounds like quite a scare! Did you dump it? Was it a night ride?

At least yours HAD moly in it. At the risk of earning everyone's scorn, here's what I ended up with. Mind you, and like I said, I'd had enough shopping for one day. Hindsight lesson learned: shop online BEFORE undertaking this spline procedure.
RED GREASE – Blastercorp
From the SDS, I'm disappointed to see that it contains zero moly but hey, at the end of my day, it was either this stuff which at least had a temp threshold of 550 degrees or some molyEP that I use on my backhoe which makes no such claims.
No, sunny day but riding a tree lined highway in and out of shade constantly. Popped out into the sun and a doe came strolling out of the ditch.

Was going to plow her right in the ribcage so I locked the back tire, counter steered in both directions and slid right around her then let off the brake.

Was the lead bike and the guys behind me only saw smoke. I was taking it easy and thinking about deer in the light conditions but almost got one anyway.

3000 miles later the threadbare spot on the tire showed up.
 

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There are numerous instances of VN750.com members, myself included, that discovered dry, reddish dust on their driveshafts when doing the initial 10,000 mile spline lube. Some assumed that spline lube was overlooked at the factory, while others thought the residue was the remnants of whatever lubricant the factory used. Unless there was some lubricant quality in the dust, those splines had no lubrication by 10,000 miles. Assuming that the factory technicians used what the engineers recommended when assembling the bikes, the recommended lubricant failed before 10,000 miles. While Kawasaki may not recommend high moly grease, it is far superior to whatever was used at the factory. Many on this forum use high moly grease because it has proven to be a suitable spline lubricant. What you have used may be fine. You will know one way or another the next time you lube the splines.
 

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So the question is, did the splines get lubed at the factory or not? Suppose there's no way to definitively answer the question, but mine looked just like the second picture mmart posted above. It looked somewhat like rust, but there was no rust scale anywhere and the splines weren't pitted or noticeably worn. Also, the residue had crumbles in it, which wouldn't be what I expected powdered rust to look like.
 
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Discussion Starter · #16 ·
There are numerous instances of VN750.com members, myself included, that discovered dry, reddish dust on their driveshafts when doing the initial 10,000 mile spline lube. Some assumed that spline lube was overlooked at the factory, while others thought the residue was the remnants of whatever lubricant the factory used. Unless there was some lubricant quality in the dust, those splines had no lubrication by 10,000 miles. Assuming that the factory technicians used what the engineers recommended when assembling the bikes, the recommended lubricant failed before 10,000 miles. While Kawasaki may not recommend high moly grease, it is far superior to whatever was used at the factory. Many on this forum use high moly grease because it has proven to be a suitable spline lubricant. What you have used may be fine. You will know one way or another the next time you lube the splines.
So the question is, did the splines get lubed at the factory or not? Suppose there's no way to definitively answer the question, but mine looked just like the second picture mmart posted above. It looked somewhat like rust, but there was no rust scale anywhere and the splines weren't pitted or noticeably worn. Also, the residue had crumbles in it, which wouldn't be what I expected powdered rust to look like.
Yes, if I saw red dust and crumbles I would have lots of questions and concerns also. It is pretty shocking seeing those pictures. Makes you wonder why some had such glaring failure, while others like mine were as expected in great condition.

I will do the spline lube every time I change the rear tire, or every 10,000 miles, whichever comes sooner, and use MDS as available. Thanks for pointing this out.
 

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I don’t know what the previous owner did, I picked up the bike with 18k miles on it and got around to getting this checked around the 21k mile point (thanks to the forum!) the guy who did it for me direct quote was “bone dry not a lick of grease on em”. He took the pics because he was surprised. I’m aware of it now so I’ll definitely check it again in a year or so.
 

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I got my Vulcan with less than 8,000 miles on it. The PO had just spent $1,400 at the Kawasaki dealership having "everything checked and put in tip-top condition". When he got it back after four months, the throttle was sticky and hard to start and he sold it to me for cheap (turned out to be a frayed throttle cable). After joining this forum, I learned of the "dry splines from the factory" issue and checked the splines. Mine too were dry. You would think a Kawi dealership would know to check a shaft drive, but they didn't. Oh, and the tires were original and dry rotted. So much for putting things in top shape.
 
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Was going to plow her right in the ribcage so I locked the back tire, counter steered in both directions and slid right around her then let off the brake.
That must've been quite the scene for those watching. Right up there with stunt man stuff. I doubt impressing people was foremost on your mind at that moment but nevertheless - I'm impressed!
Thanks for the story.
A Harley friend of mine keeps urging me to upgrade my headlight to LED. I've seen mmart's bulb swap which looks simple enough but haven't seen yours yet. More importantly, let me ask you for what I trust will be your objective opinion. Does it really make a HUGE difference?
I realize it must make some difference and everyone who's ever talked about LEDs claims they make nothing less than a whole world of difference. And maybe they do. But I'm talking about the plug'n'play kind. I don't want to have to gut my bucket to install an LED. But if you can confirm that it's definitely worth the extra lumens and visibility - including spread angle (i.e., width for seeing deer at night for instance) - to replace the OEM bulb with an LED, then I will put that on my priority list.
 

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So the question is, did the splines get lubed at the factory or not? Suppose there's no way to definitively answer the question, but mine looked just like the second picture mmart posted above. It looked somewhat like rust, but there was no rust scale anywhere and the splines weren't pitted or noticeably worn. Also, the residue had crumbles in it, which wouldn't be what I expected powdered rust to look like.
And maybe somebody's asked this question before but as I was doing my first spline job last weekend, I couldn't help wondering just how sealed that whole shaft tube is from the elements anyway. When I pulled that boot back to expose the u-joint, I realized how loosely it fit. Seriously, if I or someone else took that bike through a fair amount of water, what's to keep any of that dry?
Thankfully, my rig was impeccable. It was clean and well-lubed with no sign of wear or rust at 29k. But even so, isn't it possible that some of your scoots had some rough (wet, muddy, etc.) rides in their pasts and that crap got inside those tubes? I could also be missing something.
 
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