Diversion or just sabotage? Dodgy 17" wheel conversion

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Irtron

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I didn't have much knowledge about Vmax specific techs like 15" rim with massive bias tyre when I bought the bike.
After reading much wheel/tyre discussion on this forum I discovered that the rear tyre on my Vmax is actually 150/70 ZR17 size that I considered a bonus which was never mentioned in the bike ads.

Well, at least until two days ago when I decided to check the rear bearings after I found that the front ones are running rough and had to overhaul the speedo drive as well that got completely stuck thus I wasn't able to turn it by hand.

I found THIS (see the pics).

The hub bearing cage's completely gone,loose balls and bits of metal all over the area. And I did 125 mph the previous day! I was lucky that the hub doesn't take much radial force and the balls were still in the races although absolutely dry.

The wheel looks like a 'divvy' conversion with the hub, the rim, d17mm axle and spacers.

The problem is that the drive side bearings both in the hub and the wheel are not sealed. They are totally exposed to the elements and the grease is held by the bearing rubber shields only.

Besides thinner axle doesn't look strong enough for the much higher load and thrust than XJ900 as well as the drive side bearing that is even smaller than the front wheel one (6203 vs 6303).

Last time I checked the bearings was in March when I changed the tyre.
I made about 5000 miles since then though.

btw, what is the best way to assess the condition of the final drive bearings?
 

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I have what looks like that same wheel, but stock axle and matching sealed bearings. What numbers are stamped on it?
 
Yea, that was on borrowed time there!

'Back in-the-day,' I had a 1980 KZ1000 (one of several KZ's) w/a Denco 4/1, I loved the sound of that bike, still makes me nostalgic when I hear a Z-bike w/a 4/1 go-by.

Anyway, I was about 400 ft. from getting onto I-95 south of Ft. Lauderdale FL and headed to Miami, on a cool, foggy winter morning. As I accelerated from a stoplight, at the front of the line, the rear wheel suddenly locked-solid! It was just like a panic stop. Thankfully, the traffic behind me was able to avoid me as I came to a stop in the middle of a 4-lane road.

I was able to pull in the clutch to get the bike to roll but the engine was locked solid. I pushed it to a nearby car repair shop, and the mechanic there happened to be a bike mechanic. I made an instant friend, and he helped me later to tear-down the motor to find the ball-bearing on the countershaft sprocket/drive side had fractured its outer race circumferentially, and completely, locking that bearing and the final drive when in-gear.

It's not what you had, but the end result would have been similar, if you had been unfortunate to keep riding. A locked-up rear wheel is no-fun. In the days of two-strokes, that was all too common, on either the street or the track. I had some similar two-stroke incidents both on and off-road.

I bet you can go to a local bearing jobber and get a fully-shielded replacement bearing set, just match the size to what you have. Buy the best ones you can afford.

Now you have a nice paperweight/conversation-starter. And it appears that final drive needs to be disassembled to remove the metal shavings, lest you get contamination into things.
 
http://www.futurebearings.com/main.htm These people are great to deal with and usually have anything I want. The prices are fair and shipping fast.
Steve-o
 
What numbers are stamped on it?

Nothing stamped anymore on that one that used to be in the hub :bang head:
It was 6004 by dimensions 20x42x12.

The wheel bearings are 6303 (17x47x14) brake and 6203 (17x40x12) drive side, both 17mm ID unlike the hub bearing that is the same Vmax' 20mm ID, hence the spacer pressed into the inner race.

The problem with stock d20mm axle is 40mm OD on the drive side. 20x40 bearing doesn't exist. The closest is 6904 which is too flimsy - 20x37x9.
The same 6004 or even 63004 (20x42x16) requires tricky wheel machining and can weaken the bearing housing with thinner walls.

It seems like I'm going to stuck with the high maintenance setup I have. The bearings are not a problem as they are general standard and any good brand have them not expensive at all unlike stock needle one.

My main concern is the bearing exposure. I'm going for a 5000 miles trip around Spain and Portugal in July. Can't imagine removing the rear wheel every now and then to check on the bearings.

I'm thinking of grooving an o-ring on the outside of the wheel drive side housing to seal the hub.

As per the spline - not sure. May be a cv boot on the spline outside and the hub (the last pic). There's about 7mm from the bevel gear crown top to the seal. Perhaps not enough for the boot clamp :ummm:
 
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'Back in-the-day,' I had a 1980 KZ1000

'A long time ago in a galaxy far, far away' I had a two stroke Czech made Jawa 634 - a legend in those days in that place. After 30000 miles the crankshaft failed and she waited for a replacement in the garage for another long time until our Far East hard-working friends supplied one. There was no other alternative in the 'galaxy' then.

It survived 250 miles and seized. Big end roller bearing failure. The rear wheel locked instantly without a warning shot when the piston starts to seize giving you a split second for clutch action.

I managed to avoid tarmac - I was commuting in town and the speed wasn't that great. Besides the bike is sluggish by archaic design anyway.

Autopsy revealed the choice of material for the crankpins - a steel textured plasticine.

I still have her in bits in the garage. 'In the galaxy far, far away...'
 
Now these may be a daft suggestions but you could:
a) Post a question on the V Max Chat (a UK site) about Divvy bearings as this is a common conversion here or
b) Take the wheel to your local Yameringha dealer and ask what is normally fitted.
 
Here's a pic
uploadfromtaptalk1403973520597.jpg
And the spoke marking that indicates wheel size. I don't know if these are marked on divvy wheels. I believe this is an fzr 600 wheel.

I have no idea why there are three of these pics. sorry
uploadfromtaptalk1403973520597.jpg
 

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Thanks Steve.
A bit too far for me though.

I wonder if they do have a non-standard 20mmx40mm bearing?

they're 10 minutes from my house if you need help at all. I could always try to swing by to get it and ship it to you if they won't ship. just lemme know. I"m near the Bellingham store.
 
Is there room to take just enough material off of the bearing seat surface on the hub to use a thicker [wider] rather than larger diameter bearing and add a grease and dust seal? Just a thought.
 
Is there room to take just enough material off of the bearing seat surface on the hub to use a thicker [wider] rather than larger diameter bearing and add a grease and dust seal? Just a thought.
P.s. glad you are ok! I had a rear hub failure on a ktm off roader once. The hub came apart at about 90mph. Felt like the tire was coming off the rim. Still get chills over that one.
 
There have been a few posts about the Yamaha Diversion conversion (rhyme-time) and the pics at the beginning of this thread bear viewing by anyone who has this type of mod in-mind. Given the mechanical carnage shown via these pics, you should consider there are far-better ways (safer, too) to get a larger-diameter,/larger width tire fitment.

VMax Diversion wheel bearing failure.01.pngVMax Diversion wheel bearing failure.02.pngVMax Diversion wheel bearing failure.03.png
 
I wanted to do this because there are pics of these everywhere on Vmax. Has little to do w Width, these things are 10 lbs lighter and with Commander 3s
a 631 lb bike goes to 600. What exactly is unsafe?
 
I did not get a spacer with the 1st rim subsequently it reassembled w/o any chance of the bearings actually working.
Moreover I did find 20/40/.5 Nonstandard bearings... the local place sold me drop ins (17/37/.5)
I put many miles on this config.
Punching out the tapered core to
take a slightly larger spindle, with spacer.
 

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