Rear End Questions:

[videoarizona]

Got bike on center stand and both mufflers off, right side stripped down. Once my buddy comes by this morning, I'll get the wheels off and take them to Tucson for new rubber. After I get back, I'm going to take the rear end apart to inspect, clean and grease.

 

Question #1: at what point do I need to drain the rear end oil? I assume it's when I take the rear drive unit apart? I see it has oil seals.

 

Question #2: If I have the front end down on forks (kneeling)... if I have a broken shaft (intermediate?),do I need to drain engine oil before taking the shaft out from the trannie case?

 

Manual isn't that good...and I really don't trust it. Trust you guys and gals expertise more!

 

TIA,

david

 

P.S. that nut on rear axle is on there tight.....geesh.

[frankd]

On mine, I usually drain the shaft unit (rear end unit) while it's still on the bike. It's easier and less messy. Plus there is a small vent hole between the shaft unit and the shaft coupling area, and if you don't drain the unit and then set it on it's side, 80W will flow into the coupling. On Mk II bikes, when you pull the shaft drive unit, the driveshaft will come out with the shaft unit, because the coupling seal keeps it from coming out of the rear coupling. To remove the driveshaft from the shaft unit, just pull the driveshaft firmly. Some people replace the driveshaft seal, others re-use it. Grease both ends of the driveshaft with thick molybendum disulfide grease. Some say the best type is from Honda, but I don't remember the exact type---you can find it by searching this site. No, if you want to pull the intermediate drive gear, you have no need to drain the engine oil. Remove the swing arm (just remove the bolts in the center of the swing arm bearings) and then remove the 3 bolts that mount the intermediate drive unit. Then there are 2 engine case bolts, one on each side of the intermediate unit----loosen these bolts and remove the intermediate unit. Don't loose the spacers because you'll need to re-install them.

[videoarizona]

Perfect...thanks Frank!

[Venturous Randy]

Do you mean you want to disassemble the final drive or remove it? Unless you have a seal that needs replacing, I would not take it apart if I removed it from the bike.

If you have the bike on the center stand with the front wheel off, make sure you have a strap or something pulling the center stand forward so it can not collapse on you.

The driveshaft does not go into the transmission, it goes into a U-joint.

Unless I missed something, what is the problem with the bike other than replacing tires? Do you think you have something broken?

RandyA

[KIC]

Here is what I used when I did mine. Some of the drive shaft info is at the end of the tire removal part. Also, remember to not tighten the 4 final drive bolts until the tire and rim are installed and the axle is tight. Then tighten the 4 bolts.

 

 

REAR TIRE REMOVAL.doc

[videoarizona]

Randy,

 

I want to check the intermediate shaft to see if the shaft broke. I have a small leak under the ujoint area and have a loud whine under deceleration. So there is the potential issue of the shaft broken and the end and nut riding inside the ujoint.

 

So taking the differential off, pulling the drive shaft out from ujoint is important to me at this point. Why not? I'm this far anyway. And...found out the rear end oil had never been changed (39K miles), or not changed in some time, as it was black and some metal filings on the little magnet end of the drain bolt. I took delivery in April and have been working on it to check it out a little at a time....

 

[Venturous Randy]

You just described the conditions of a broken pinion nut. If this is the case, you will do better to pick up another final drive, which you can find pretty cheap on ebay. There are also several V-Max final drives as low as $89 with free shipping.

I have never heard of a broken pinion nut on an MKI, but I have seen sevaral on an MKII. I have also never heard of one on a 2nd gen.

RandyA

Edited December 5, 2014 by Venturous Randy

[videoarizona]

Bill, thanks for the doc. It seems I already downloaded that and printed it out! Had it sitting on the floor next to the tools...and a pencil to check off the steps.

If I do have an issue, I'll be giving you a call, Bill, if you don't mind. Probably not until next week as I need to be in Payson this weekend.

 

Frank, I looked over the manual and the pictures of the swing arm mounts... and it doesn't look as easy as four bolts. I'm going to see if I can pull back the rubber boot and check out the ujoint and intermediate shaft nut first. If all is well, I won't bother with the swing arm. I'll only pull the rear end and check the drive shaft. If my memory is correct, the rear end splines of the drive shaft are bathed in oil from rear end (1st gen 1989) so only the front end of the shaft needs grease.

 

Randy, I'll see if the rear end is OK...don't think I've heard to much about older 1st gens having that issue either...I'm going to think about taking the rear end apart. Everything "looks" good from outside, including bearings on wheels, etc.. But who knows what evil lurks under the skin?? Wish there was an easy way to confirm a broken pinion nut?

 

Anyway, taking everything apart was easy with your help...wheels are back from Tucson with new Shinkos at 44 pounds of pressure so they should be good.

Will keep you posted...

[Venturous Randy]

Randy, I'll see if the rear end is OK...don't think I've heard to much about older 1st gens having that issue either...I'm going to think about taking the rear end apart. Everything "looks" good from outside, including bearings on wheels, etc.. But who knows what evil lurks under the skin?? Wish there was an easy way to confirm a broken pinion nut?

 

Anyway, taking everything apart was easy with your help...wheels are back from Tucson with new Shinkos at 44 pounds of pressure so they should be good.

Will keep you posted...

Since you already have the rear wheel off, it only takes a couple of minutes to take the four nuts off the final drive and pull it off and then you will know.

RandyA

[skydoc_17]

Hey David,

Randy is correct! Remove the 4 nuts from the Final Drive that connect it to the Drive Shaft Tube, and if the nut is broken, you will be able to see it plainly. If the nut is broken, and you have been hearing the rear growling, there is a pretty good chance the Pinion bearing is shot, not to mention the Pinion Gear could be damaged. The only thing you can service in the Final Drive is the oil, and it sounds like you have done that. (Short of a major overhaul of the Final Drive, ie Ring Gear, Pinion Gear, bearings, Setting Ring to Pinion lash, $$$ etc.) This is why Randy suggested picking up a used Final Drive. Much more cost effective.

Earl

[KIC]

Would a final drive from an 84 work on a 89 MKII ?

[Venturous Randy]

Would a final drive from an 84 work on a 89 MKII ?

It should work, but you will also have to use the 83/85 driveshaft. You would also need to do a good lube job on the shaft splines everytime you change the rear tire.

RandyA

[KIC]

It should work, but you will also have to use the 83/85 driveshaft. You would also need to do a good lube job on the shaft splines everytime you change the rear tire.

RandyA

 

Thanks Randy for the info. Why is it that an 84 needs to be lubed more often than a 89 ??

[Prairiehammer]

Why is it that an 84 needs to be lubed more often than a 89 ??

 

The 1986-2013 Venture rear drive shaft splines are lubricated by the final drive gear oil. The 1983-1985 Venture rear drive shaft splines must be hand greased. The front drive shaft splines on either version should be hand greased.

[videoarizona]

Thank you gentlemen....I will pull the rear off when I come back from Payson.

Will keep you all posted...

david

[videoarizona]

Well...couldn't stand the suspense: Took the rear end off. No sign of damage on the pinion side or the ujoint side (at least as far as I can see. The drive shaft turns the rear end quietly and smoothly. Pictures attached. Couldn't find a way to get in there to get the rubber boot pulled back enough to see if the intermediate gear/shaft/nut is broken or not. But from the picture I took down the drive shaft tunnel, sure can't see any evidence of a nut with a shaft end attached sitting in the middle of the ujoint!

 

Seal looks good, splines look good. I'm going to stop now and get ready for working weekend in Payson(putting new deck boards in, etc.)

In order: Seals and pinion nut, rear end drive, rear end side of drive shaft, ujoint side of drive shaft, peaking down the tunnel at ujoint.

 

 

[Prairiehammer]

Something don't look right.

The coupling should not have come off with the drive shaft. And looking at the final drive input, it appears that your final drive input (pinion) is broken. Pull the coupling off the rear of the drive shaft and I'll bet you find the forward end of the final drive pinion shaft.

[videoarizona]

uh oh.....OK..will do...

[videoarizona]

Yep...broken pinion shaft...Good catch Randy and Kevin!

 

I'll start repairs when I come back. Thanks Kevin for conversation!

[KIC]

Ok, excuse my ignorance on this issue. But is his broken shaft (just the broken piece) interchangeable with one off of an 84 ? The reason I keep asking is that I have two 84 parts bikes and if David can use any of the pieces, we can easily take them off one of the bikes.

[videoarizona]

Bill,

From what I understand, the earlier models had a different drive shaft arrangement. Yes it would work, but more parts need to be replaced to make the shaft fit. I don't know if the swing arm will work as some the the earlier swing arms are different design as well. I don't know if the entire rear end is a simple drop in repalcement.

 

Thanks for the thoughts, though! I just ordered one from EBay..(before I read your post)

 

http://www.ebay.com/itm/231338042061

 

Due in on the 15th of Dec.

First thing I will do is check the bearings and the pinion shaft!!!

[frankd]

There is a difference of opinion as to whether on the MKII bikes the rear driveshaft spline is lubricated by the shaft drive unit or not. I believe that it's not, and that you'll find 80W on the coupling only if you don't drain the shaft unit before you pull it, and then when you set it down sideways, the 80W flows through the vent into the coupling. I don't want to start another argument about this, but....look at page 6-70 in the MK II manual.

 

http://labs.trunkful.com/vrmanuals/firstgenmanual.pdf

 

and you can see that Yammie wants you to lubricate BOTH ends of the driveshaft with molybendum disulfide grease. That implies to me that the rear coupling is NOT lubricated by 80W from the shaft unit.

 

Seeing that you have an oil leak underneath the intermediate drive unit, and you have a severe gear whine under deceleration, I suspect the shaft the u-joint attaches to has broken. I can't say for sure if you'll be able to tell if it's broken or not just by inspecting it without dis-assembling it, but see if the nut is still atached (forward of the u-joint) and that you can't detect any in and out play. Make sure that your oil leak is indeed from this shaft, not the rear valve cover. On my 83 (they are identical here) I did have the seal go bad and I had an oil leak here. I changed the seal and all is fine. On my 89, when my u-joint self destructed (very dry bearings), I also replaced this seal for preventative maintenance. I don't remember that it was difficult to pull the swing arm loose. After you get the shaft drive unit and the driveshaft out, remove the bolts that attach the rear suspension to the swing arm, and then remove the bolts that go through the center of the swing arm bearings (underneath the rubber plugs. I think I remember that they have nuts on the inside and one of the bearings has an adjustment mechanism. Inspect these bearings and make sure they rotate smoothly. Mine were very notchy so I replaced them.

 

If your intermediate drive unit is good, but you have an oil leak, I'll write a trick I used to make sure it went back together with the same bearing preload.

Edited December 5, 2014 by frankd

[Prairiehammer]

There is a difference of opinion as to whether on the MKII bikes the rear driveshaft spline is lubricated by the shaft drive unit or not. I believe that it's not, and that you'll find 80W on the coupling only if you don't drain the shaft unit before you pull it, and then when you set it down sideways, the 80W flows through the vent into the coupling. I don't want to start another argument about this, but....look at page 6-70 in the MK II manual.

 

http://labs.trunkful.com/vrmanuals/firstgenmanual.pdf

 

and you can see that Yammie wants you to lubricate BOTH ends of the driveshaft with molybendum disulfide grease. That implies to me that the rear coupling is NOT lubricated by 80W from the shat unit.

 

Frank, I think the procedure in the manual refers to when reassembling a rebuilt, repaired or otherwise unlubricated final drive. Call it pre-assembly lube.

This Yamaha Technical Bulletin specifically says that the 1986-1992 (the Tech Bulletin was written in 1992) rear drive shaft splines are lubricated by the final drive oil. (See lower left paragraph.)

[frankd]

Kevin,

 

I guess I'm wrong. I never saw that technical bulletin before. Thanks for the info!!

 

Frank

[videoarizona]

Frank,

 

My driveshaft differs from the picture in the manual. My 89 driveshaft has a circlip on the rear end of the driveshaft. That holds an oil seal between a round thin plate on one side(clipring side) and the gear at the end of the drive shaft. There is another oil seal inside the rear end assembly between the main gears and the coupling. Thankfully, I did as you suggested and drained the oil from the rear end prior to dis-assembly. There was residue oil left over inside the coupling unit and on the drive shaft rear gear. So I think the rear end of the drive shaft is in an oil bath. Without the seal between the gear and the clipring, then I would assume the gear needs to be lubed by grease.

 

 

 

I agree and need to take off the swing arm to see what is going on there. If broken, then repair. If not broken then decide whether I want to continue to tear down intermediate gear to replace the oil seal...be nice if the "O" ring was bad...that would be too simple!

 

I did spend more time under bike this morning and figured out what you described to remove the swing arm. Kevin gave me some additional hints there was well....so that won't to hard.

 

Bill, I don't think I answered your question fully. To whit: Yes, if the swing arm is the same design, I should be able to take the entire rear end and drive shaft and just swap them out. I simply didn't remember you had parts bikes!!! So I went on EBAy asap and found an entire unit from a 91.

I would rather have paid you for parts then wait a week to get something I don't know how good it is.

 

Well, off to get some wood working done!

Have a nice weekend gentlemen...be back Monday evening or Tuesday.

Thanks,

david