strange bounce

[i-man]

Ok, this is something I hesitate to say, because i don't want you fine folks who have helped me so  much  to give up on me. But I'm a dumbsass. The reason the axle was hard to remove is I didn't have the front tire far enough off the ground! :dunno2:

I jacked the front up more and the axle comes out as easy as it should!

Hasn't solved the problem, but i feel even more certain that it's not stiction.

[Motorhobo]

Don't beT yourself up. I've ridden with loose lug nuts about to fall off and still do stupid shit like ruining a perfectly good paint job by ripping tape off too fast. That was last week.

[Dennis de Vries]

Not to worry, we all have those "duh...." moments, not all of us are man enough to admit them though...

[i-man]

thanks y'all.
I really appreciate people taking time to give thoughtful answers. I'd like to at least meet them half way!

[i-man]

latest---I took the tire off the rim, put the rim back on the bike and spun it. The rim wobbles. I don't have enough experience with cast rims  to say if it wobbles a lot or a little, but you don't have to look hard to see the wobble.

Is it normal for there to be some wobble?

I inspected the tire inside and out and theres nothing obviously wrong with it. my plan now it to  re-mount the tire, take it to a shop to have it balanced.

Unless someone thinks that any noticeable wobble of the rim points to some another problem.

[johnny]

greetings i-man...

sounds likes you needs to score a true straight front wheel or getts yours to a good wheel man... or both...

j o

[Motorhobo]

I'm still hung up on what you said about this first appearing while riding with loose pinch bolts. If that's true it's a mighty strange coincidence that front end wobblies would not be related to that event.

[i-man]

yes, I feel the same way about the pinch bolts thing. But I don't know how it would effect it, and everything seems tight and straight, and I'm not sure how to test to see if it was caused by the pinch bolts being loose, so I see trying to balance the wheel as being worth a try.  If anyone with more experienced then me has an opinion, please let me know.

I need to add something that I've over looked to this point. There were a lot (10 to 12, I think) balancing weights on the front rim before I took them off and tried the Ride On. Two of the weights were missing (residue where the weights had been). But at the time I didn't think two weights out of that many would effect the balance in such a profound way.

Is it possible the the rim was so out of whack that they loaded it up with weights to get by? I know a lot depends on the weight of the balancing weights, but is 10 to 12 weights a lot, or pretty standard?

Can a cast rim be straightened? Is it more or less costly then finding a true use rim?

[Motorhobo]

Maybe you can put the wheel on a dowel or pipe or something and see if it spins true there. If it does, you have an issue with the axle or fork alignment. I don't know if that would work...anybody every try that or know why it's a fail?

[i-man]

without knowing much about the process, I'm hoping that if I take it to a shop to have them balance it, they'll either give it back to me saying it's been done, or say that the rim is screwed up and can't be balanced. but I like the idea of doing it on on some stands, if possible.

[Novafrk]

I recently had a front wheel balanced, it used 2 oz of weights... I have a bounce in my front end after installing the new tires. The rear shock gave up the ghost about the same time so I was banking on that being my issue. 2oz of weight seems a lot to me though, considering the rear wheel took 0 oz of weights. I may break the beads and turn the tire 90-180 deg and have it re balanced... 12 weights on your wheel, assuming they are .25oz weights would be 3oz, missing a half an oz I would think that would be enough to make it out of balance. Usually when that many weights are needed a shop will break the beads and spin the tire to try again. I mount my own so they didn't do that for me. Rambling over.

[i-man]

how do you spin the tire if it only goes in one direction?

I suspended the rim between jack stands, using a metal rod as an 'axle'. Not very scientific, but it did wobble in the exact way that it had before. So based on my very un scientific test, it seems the rim is off, which in my mind is better then the forks being messed up. I think I'll proceed with my plan to take the wheel to the shop and have them balance it and see where that gets me. Seems a low cost test.

[Motorhobo]

Pondering whether the wheel bearings could get out of whack after riding with loose pinch bolts. I have a hard time understanding how a cAst metal rim could warp with no visible damage. It's not like it's a spoked bicycle tire.

[johnny]

motobrick wheels are soft... they go whack near the bead by novice tior techs and by hitting holes and debris in the road...

aints whacked a front one... butts whacked 2 rear ones... disposed of one and had one trued...

j o

[Inge K.]

motobrick wheels are soft... they go whack near the bead by novice tior techs

+1....Especially early Y-spoke with concave sides...............on my oldest K the front rim was damaged when removing the factory mounted tires...ie, first tire/tyre change.

[bocutter Ed]

motobrick wheels are soft...

dropped my front about 2 feet onto a concrete floor (buttered fingers). Took a bit of work with a 2x4 and 8 lb sledge to straighten it out.

Were the pinch bolts loose after a tire change, by chance?

[i-man]

thats a good guess, but no. The fairing was cracked up and I took it off and put a aftermarket headlight on. I took the front wheel off to slide the forks down to get the bracket for the headlight on. that's part of the reason for the confusion. many things happened that could have been the cause. messed with the forks, messed with the front wheel...but then rode it for several miles after and it felt fine. then the bounce. then noticed the pinch bolts. don't know if its related.

[i-man]

took the wheel in and had it professionally balanced. Didn't fix the problem, but it made it much better.

not really sure what to do next. The obvious answer is to take it to a professional, but I'm not ready to throw in the towel.

[Motorhobo]

Maybe find another wheel and put it on and see if the problem persists. Sounds like you haven't yet determined whether the problem is in the axle, the wheel or the fork structure.

You should put your location in your signature, maybe there's someone near you who can volunteer assistance but not if nobody knows where you are.

[Novafrk]

FWIW, Just installed my new shock. I did a quick ride around the block and didn't notice the bounce that I had. I ran it up to 40 mph where it seemed to be the worst... nothing nada, no bounce. Just to confuse the situation some more.  :falldown:

[i-man]

i tried to ad my location to my profile, and for the life of me a didn't see that option.
anyway, I'm in Durham NC.

Good for you Novafrk. It gives me hope.

[Motorhobo]

Location is under the Forum Profile link under the map all the way at the bottom of the page.

[racinrich]

just following your diagnostic path , so with the new rear shock the condition is fixed resolved gone and life is good ???

[Novafrk]

It seems to have gone away yes. I only ran it around the block once but the porpoising feeling in the bars seems to have gone away.

[i-man]

It's over! got a new (used) wheel and the bounce is gone! I put about 50 glorious bounce free miles on it today!

I think i originally slung a couple of the wheel weights and that caused my damaged wheel to bounce. There was probably some bounce all along, but I let it go because it was an unfamiliar bike, but minus a couple of weights it was undeniable. Then I went down a bunch of blind alleys, such as stiction, loose pinch bolts and so on.

Anyway, All's well that ends well!