Jump to content

rear wheel woes


Guest hogjockey

Recommended Posts

...measure ACCURATELY the distance between the two bearing registers in the wheel and have a proper spacer machined from 2.5mm wall tube to that EXACT dimension +0.25mm....

 

Pete - what's the +0.25mm for - to allow for compression in the spacer????

 

KB :sun:

Link to comment
Share on other sites

snip

What is a problem, at least on 1100 Sports it is so I'd guess it's likely that the V11 is the same, is that the bearing spacer that goes between the bearings, rather than being made of a decent bit of steel pipe, is made of thin tube with a couple of crappy pressed tin *flanges* on it to help prevent it dropping into the wheel when the spindle is removed. Not only is this bit of shit so flimsy as to be almost impossible to machine accurately, (If it is?) it is so weak that even torquing up the spindle a bit vigorously would be more than sufficient to cause it to deform, it's easy to put hundreds of pounds of pressure on such a thing with a good heave on the spindle nut!!!! If the tube, which may or may not have been long enough in the first place, deforms and the outer races of the bearings seat fully home on their registers in the wheel itself as the nut is tightened the inner races will be pulled inwards and the bearings will be asked to take a side loading they were never intended too. Result? Lots of friction, lots of heat and rapid bearing failure.

 

So why does this aflict 1100 Sports and V11's more tha any other machine? The simple answer is that they are made cheaply and poorly, sad but true. Once again this is an example of crappy execution of a very simple piece of engineering, it's a bloody wheel for fucks sakes, not the space shuttle!!!!!

 

If you want a cure, once and for all, measure ACCURATELY the distance between the two bearing registers in the wheel and have a proper spacer machined from 2.5mm wall tube to that EXACT dimension +0.25mm. Get a pair of poxy 2RS/C3 bearings of the correct type, stick 'em in and forget about it for 100,000Km!!!!

 

Pete

56575[/snapback]

Pete,

Problem one is that people like me are too inept to measure ACCURATELY, and too cheap to pay $100 for a machinest to make a proper spacer out some overweight carbon steel.

We have an opportunity here to get something lighter, stronger, and of the proper dimension.

Yah each of us could go out and buy a thirty dollar micrometer, tear our wheel apart, measure, take the day off work to go bug the machinist who will take diddly long to order and cut a 1inch OD pipe with a 2.5mm wall, wait for the snow to fall and then get our bike back together.

Or we could do what we are doing here, join forces, and come up with a superior spacer for less money and little down time.

If we are going through the trouble of paying a machinist, we may as well have it made from a proper material and not the poxy crap used in the V1100 and possibly our bikes.

If it is space shuttle quality alloy in an unsprung weight situation, than it will be all the more better.

I may even be one of the one percenters that will go with the $100 bearings. After shipping and the labor of the project, it will only increase the cost 30%, but I will have the slickest bearings in town :cheese:

Regardless, the difference in price between steel and aluminum is negligible, assuming we can find the appropriate stock.

From what you said, the material can be too weak and fail under the torque from the axle nut. That is one of our concerns (apparently not Guzzis) which is why we need feed back from someone with your expertise.

I got scolded for using non-graded aluminum :blush:

That is why we have to go through this to get it right.

Apparently we don't have any aerospace engineers reading this that could say whether or not the alloy could hold up to the compressive forces...either that or they are maniacally laughing at us from behind their keyboards. :lol:

So far we found something too thick and something too thin in aluminum.

If I read your advice correctly, you suggest a decent quality steel 2.5mm wall thick.

You are suggesting steel, right? I am assuming that because of the space shuttle comment.

2.5mm thick with 1inch OD stock will tight on the axle, but should do the trick with a good bevel job.

Unless someone can say with authority that tempered aluminum alloy is fine, than maybe we should do what you recommend.

I think we have accurately enough measured the distance to be 112.8,(possibly smaller) so 113.05 may be just what the Roper ordered :P

Or if we go with an alloy, we may need a greater safety margin, as it may compress more. What the heck, we just need some material spec sheets that we can understand and then we can get this bloody space sh^ttlle off the ground! :rasta:

Link to comment
Share on other sites

Pete,

Problem one is that people like me are too inept to measure ACCURATELY, and too cheap to pay $100 for a machinest to make a proper spacer out some overweight carbon steel.

We have an opportunity here to get something lighter, stronger, and of the proper dimension.

Yah each of us could go out and buy a thirty dollar micrometer, tear our wheel apart, measure, take the day off work to go bug the machinist who will take diddly long to order and cut a 1inch OD pipe with a 2.5mm wall, wait for the snow to fall and then get our bike back together.

 

I may even be one of the one percenters that will go with the $100 bearings. After shipping and the labor of the project, it will only increase the cost 30%, but I will have the slickest bearings in town :cheese:

Regardless, the difference in price between steel and aluminum is negligible, assuming we can find the appropriate stock.

From what you said, the material can be too weak and fail under the torque from the axle nut. That is one of our concerns (apparently not Guzzis) which is why we need feed back from someone with your expertise.

I got scolded for using non-graded aluminum :blush:

That is why we have to go through this to get it right.

Apparently we don't have any aerospace engineers reading this that could say whether or not the alloy could hold up to the compressive forces...either that or they are maniacally laughing at us from behind their keyboards. :lol:

So far we found something too thick and something too thin in aluminum.

If I read your advice correctly, you suggest a decent quality steel 2.5mm wall thick.

You are suggesting steel, right? I am assuming that because of the space shuttle comment.

2.5mm thick with 1inch OD stock will tight on the axle, but should do the trick with a good bevel job.

Unless someone can say with authority that tempered aluminum alloy is fine, than maybe we should do what you recommend.

I think we have accurately enough measured the distance to be 112.8,(possibly smaller) so 113.05 may be just what the Roper ordered :P

Or if we go with an alloy, we may need a greater safety margin, as it may compress more. What the heck, we just need some material spec sheets that we can understand and then we can get this bloody space sh^ttlle off the ground! :rasta:

56617[/snapback]

 

Unsprung weight????? Mate you've got a sodding great GEARBOX on the rear wheel spindle, do you really think the few grams difference in weight between aluminium and steel in the spacer is going to make the teeniest bit of differenece????? :grin:

 

Really, there is no need to be getting the distance between the bearing registers measured to microns! All you need to do is ensure that when the spacer is installed it is ever so slightly LONGER than that distance so that when the bearings are installed they, or at least one of them, will be slightly off the register. When you tighten up the axle nut what you are doing is effectively compressing a whole series of spacers. (I'm doing this from memory so there may be something I miss, if so I apologise.) There is a shoulder on the spindle that goes through the brake caliper carrier, this presses against the LH wheel bearing inner race, that presses against the spacer inside the wheel, then that presses against the inner race of the RH wheel bearing which in turn presses against that stupid, useless, and to my mind completely un-necessary washer in the interior of the bevelbox. That presses against the spacer in the B-Box housing which, (I think.) then presses against the outer race of the crappy needle roller and finally there is a washer and then the nut. as you tighten it it's just like tightening a nut on a bolt wth a stack of washers on it. They all get clamped up together.

 

Now the bearings themselves are only a push fit into the wheel. A fairly tight push fit but as you know it doesn't take much to remove them. They don't have to be tight in there because their position in relation to the centreline of the bike is kept correct by the lengths of the shoulder on the spindle and the various other spacers being clamped together. The wheel itself can't "Fall off" the bearings because if it tries to move left on the bearings the register of the left hand bearing will prevent it. Likewise if it tries to move right the register of the right hand bearing will prevent it The loadings caused in this situation are pretty low. Ball races like the wheel bearings CAN take a small amount of side loading and they are more than up to taking these sorts of pressures, remember that most of the loads on the balls will be in line with the bearing due to the weight of the machine and the working of the suspension. Side loadings in service are very low and are mainly down to overcoming the gyroscopic forces of the wheel and tyre as you counter-steer like buggery to go round that bend :bike: .

 

What will kill them really quickly as I said is if the spacer is too short. If it is then when the bearings are installed they will BOTH settle on their registers in the wheel but because the spacer is too short when the nut is tightened the inner races will be pulled in towards the centre of the wheel until large side loadings are imposed on them, deforming the balls, preventing them from rolling and denying them lubrication as they skid around the races. Result? Very rapid failure!! We had this problem with the front wheel of the race bike early on due to it's odd front hub!

 

"Ah" I can hear you thinking, "But if the wheel bearings are free to *move* in the wheel without being clamped in the registers then surely the wheel won't remain on the centreline of the bike!?" Well, yes, if you had say 2mm of extra length in the spacer that might well be the case. The wheel would have a tendency to *walk* about on the bearings and in all probability it would very soon wear the wheel out around the outer races, not to mention the fact that centreline of the tyre would be moving around the centreline of the machine misalighning the wheels, (Although to be honest I don't think it would be very noticeable, I've seen machines with lots more off-centre than that come out of crates from the factory!). Because though, if the spacer is correctly made so there is only a fraction of a mm clearance once the bearings have settled, the bearing clearance, the friction of the outer races in the wheel and the very minor loadings will mean that the whole sorry box and dice won't move once it has settled and self centred. or if it does the movement will be so small and so infrequent as to mean that no damage will occure within the predicted lifespan of the wheel.

 

When I suggested 2.5mm thickness this was for the wall of the spacer, obviously it's ID needs to be ever so slightly bigger than the wheel spindle but not so large that it can be misaligned on the bearing inner races. I suggest a wall thickness of 2,5mm simply because I reckon that that would be more than adequate to take the compressive forces imposed by the nut when done up by an over-enthusiastic tyre-changing pimply a your average Wottalottacrap-Discount-Tyre-and-Pornography emporium in downtown Turdpoke!

 

Bearings are bearings are bearings! They are all made to ISO standards and as long as the bits they are fitted to/in/with are properly made you'll find that this is such a low speed/low stress situation that even the cheapest and nastiest of them should last pretty much forever! Like all bearings I tend to buy ones from reputable manufactures, SKF, Timken, NSK, NTN etc. and try to avoid ones made by some unknown firm based in Boongo-Boongo land, common sense really. I have to say that I can't remember the last time I saw a wheel bearing fail? About five years ago on a twenty five year old T3 I think :grin: .

 

Measuring the distance doesn't need an expensive micrometer, just use a vernier caliper, then measure the spacer you have and see if it's too short. Any wombat with a crappy old Myford can turn up a wheel spacer in a three jaw chuck in about five minutes, all it takes is a bit of pipe with the right ID. As I said the length doesn't even have to be *exact* as long as its a smidge over the length of the distance between the registers so the inner races aren't clamped.

 

Now stop worrying and working yourself into a lather and go and do a couple of simple measurements, go to the local metal-mart and have a dig through the off-cuts bin until you find a bit of mild steel pipe with the right ID, take it to someone with a lathe, get the OD turned down to the correct size and then part it off the right length. Dress with a file to get the burrs off, drop by the bearing shop on the way home, biff it all back together, go for a test ride, come home, drink beer!!! :bier:

 

Pete

Link to comment
Share on other sites

............ Any wombat with a crappy old Myford can turn up a wheel spacer in a three jaw chuck in about five minutes...../quote]

 

damn....two attempts, a 4 jaw chuck & even then i got it too short...

Link to comment
Share on other sites

Guest ratchethack

Hey Dave, sounds like Pete must've dropped another Ambo flywheel on his foot today. :whistle: How you doin' after bein' worked over like that, my friend?! But as usual, the man presents well-articulated points and unarguable logic - not to mention a year or 2 of depth in his field - all that, and he still gets my laffer goin' every time. :grin:

 

Hey Keith - Reckon if you were a wombat with a crappy old Myford you'd a' got it right the first time...? :lol:

Link to comment
Share on other sites

Hey Dave, sounds like Pete must've dropped another Ambo flywheel on his foot today. :whistle:  How you doin' after bein' worked over like that, my friend?! 

 

Sorry if I gave offence? There was no intention to 'Work anyone over' :blush:

 

Pete

Link to comment
Share on other sites

Now stop worrying and working yourself into a lather and go and do a couple of simple measurements, go to the local metal-mart and have a dig through the off-cuts bin until you find a bit of mild steel pipe with the right ID, take it to someone with a lathe, get the OD turned down to the correct size and then part it off the right length. Dress with a file to get the burrs off, drop by the bearing shop on the way home, biff it all back together, go for a test ride, come home, drink beer!!! :bier:

 

Pete

56623[/snapback]

You make it sound so easy. :luigi:

Can't I just pay someone to do it for me. :nerd:

I am trying to sucker JRT into it, and you are messing the whole thing up. :angry:

So after all this, we are probably going to end up making that unsprung boat anchor even heavier....good grief :drink:

I don't know where the local Metal-Mart is, probably next to the Wottalottacrap-Discount-Tyre-and-Pornography emporium in downtown Turdpoke!

But I do know where the beer mart is, so I'll give twenty US bucks to the first person to ship me what Pete said. :bier:

And just so you don't have to do the measuring, have it made 113.0mm.

Thanks!

Oh, and I just went to the best hardware store in SanDiego, Marshall's, and I couldn't find anything in steel that would make the grade.

Their thick walled 1inch OD seamless steel was 1mm too small on the ID....DRAT!

Otherwise, they had galvanized steel pipe, that looked even crappier than the OE spacer.

Yah, Pete said the Metal-Mart, not the hardware store...

Link to comment
Share on other sites

Guest ratchethack
Sorry if I gave offence? There was no intention to 'Work anyone over' :blush:

 

Pete

56628[/snapback]

Just joking, Pete. You were strictly a Gent. Besides that, Dave's a BIG boy. He can take it... ^_^

Link to comment
Share on other sites

Guest ratchethack
You make it sound so easy. :luigi:

Can't I just pay someone to do it for me. :nerd:

I am trying to sucker JRT into it, and you are messing the whole thing up. :angry:

So after all this, we are probably going to end up making that unsprung boat anchor even heavier....good grief :drink:

I don't know where the local Metal-Mart is, probably next to the Wottalottacrap-Discount-Tyre-and-Pornography emporium in downtown Turdpoke!

But I do know where the beer mart is, so I'll give twenty US bucks to the first person to ship me what Pete said. :bier:

(snip)Yah, Pete said the Metal-Mart, not the hardware store...

56629[/snapback]

Stop it, you Guys are killin' me. Dave, there used to be a Metal Mart in National city...

Link to comment
Share on other sites

Oh, and Ratchet, thanks for dropping by and helping me with something as simple as measuring sag.

After you left, I set it to ~2mm bike only and ~27-28mm with my @ss in the saddle...assuming what we discussed regarding ratios, etc.

I still have to see if it bottoms too easily.

Link to comment
Share on other sites

What's the required ID???? I'll see if i can knock you ups something next week if you like?

 

Pete

56633[/snapback]

20mm minimum. Maybe 21mm ideal.

But don't you worry Pete, I have confidence in JRT running off a batch.

However, if he does not, UPS from Australia, may be doable.

Thank You sooo much for the offer.

I probably have another month before I have to change the rear tire.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...