creaking for rear end with new mods

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id try another radial rime, or different notched arm. can you install all but with out drive shaft then tighten everything to try and isolate noise
 
Just a thought Garrett....have you, or can you measure the length of both s/a's, from a point in the pivot's to the flange the diff mounts to?

Is there any possibility the new arm is a little shorter and a spline is mating in a new spot, or something wierd like that? :ummm:
 
id try another radial rime, or different notched arm. can you install all but with out drive shaft then tighten everything to try and isolate noise

unfortunately no access to either until i get another arm.

the problem typically only appears once the rear diff is warm, but i could try installing the rear diff without the driveshaft. problem is i feel like the hypoid oil would get EVERYWHERE without the shaft in to seal it. any ideas?

Just a thought Garrett....have you, or can you measure the length of both s/a's, from a point in the pivot's to the flange the diff mounts to?

Is there any possibility the new arm is a little shorter and a spline is mating in a new spot, or something wierd like that? :ummm:

no clue but thats easy enough with a tape measure right? i'll add that to the list for the am. hopefully can find a point to measure off the new arm when its in the bike. sick of pulling the arms.
 
ya guess if you have it all together and drain the oil and it still makes noise, then taking out the shaft with no oil might lead you to something
 
unfortunately no access to either until i get another arm.

the problem typically only appears once the rear diff is warm, but i could try installing the rear diff without the driveshaft. problem is i feel like the hypoid oil would get EVERYWHERE without the shaft in to seal it. any ideas?

Wouldn't the oil seals prevent that Garrett?



no clue but thats easy enough with a tape measure right? i'll add that to the list for the am. hopefully can find a point to measure off the new arm when its in the bike. sick of pulling the arms.

Pull the pivot cover and measure from the backside of the hole to the final drive flange? :confused2: Tape measure should be fine, just be sure it's in the same position on each arm.
 
Pull the pivot cover and measure from the backside of the hole to the final drive flange? :confused2: Tape measure should be fine, just be sure it's in the same position on each arm.


the driveshaft has the seal on it.

yea i'll check that altho i doubt it'll be a problem since the old rim didn't see any issues.
 
so some good news. i put the new rim back on the bike today (creak still there). trying something i put a feeler gauge between the diff and swingarm right near the upper inboard stud. guess what? no creaking! so i'm gonna see if the local machine shop can mill it flat, fix it, or do something (keeping in mind if they mill it i'll have to make up the difference somehow).

i used a .75mm feeler gauge.
 
so some good news. i put the new rim back on the bike today (creak still there). trying something i put a feeler gauge between the diff and swingarm right near the upper inboard stud. guess what? no creaking! so i'm gonna see if the local machine shop can mill it flat, fix it, or do something (keeping in mind if they mill it i'll have to make up the difference somehow).

i used a .75mm feeler gauge.

Garrett, did you try the feelers gauge at all 4 studs or just the one? Or break the gauge in 4 pieces and place them at each stud?

You may want to go thru some more scenarios before committing to machining.
 
Garrett, did you try the feelers gauge at all 4 studs or just the one? Or break the gauge in 4 pieces and place them at each stud?

no because when loosening the acorn nuts and then retightening lightly with wrench with no lockwashers, i could see that part wanted to stay slightly out compared to the rest. so i figured why not try the feeler gauge there. i attached a pic how i put it on.


You may want to go thru some more scenarios before committing to machining.


i could, but i bet the machine shop could tell me what else is wrong with it and the amt its 'off' other studs may be off but i'm not going to be able to tell with my rudimentary tools.
 

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I know how to solve the problem in it's entirety........... CHAIN DRIVE:rofl_200::rofl_200: Strangely enough I don't have to worry about a differential making weird noises....:rofl_200:
 
Ur not helping......!

I know how to solve the problem in it's entirety........... CHAIN DRIVE:rofl_200::rofl_200: Strangely enough I don't have to worry about a differential making weird noises....:rofl_200:
 
With the diff out you could lay a straight edge horizontal across the square face of the swingarm and also place your axle in the swing arm with the large end of the axle held tight with the pinch bolt. Have a look to see if your straight edge is parallel with the axle. From what you have described with the gap in the diff when it is offered up to the swingarm, my guess is that the welded brace has cantered the face of the swingarm inwards like as if your bike had been hit from the diff side of the bike at the rear of the rear wheel.
You could check these measurements versus your stock swingarm for comparison.
 
With the diff out you could lay a straight edge horizontal across the square face of the swingarm and also place your axle in the swing arm with the large end of the axle held tight with the pinch bolt. Have a look to see if your straight edge is parallel with the axle. From what you have described with the gap in the diff when it is offered up to the swingarm, my guess is that the welded brace has cantered the face of the swingarm inwards like as if your bike had been hit from the diff side of the bike at the rear of the rear wheel.
You could check these measurements versus your stock swingarm for comparison.


thats an easy enough test. i'll see if i can get her done tonight.
 
With the diff out you could lay a straight edge horizontal across the square face of the swingarm and also place your axle in the swing arm with the large end of the axle held tight with the pinch bolt. Have a look to see if your straight edge is parallel with the axle. From what you have described with the gap in the diff when it is offered up to the swingarm, my guess is that the welded brace has cantered the face of the swingarm inwards like as if your bike had been hit from the diff side of the bike at the rear of the rear wheel.
You could check these measurements versus your stock swingarm for comparison.

so i think we finally found it. i clamped a level to the swingarm flange and using methods that would make any machinist cringe i got the following. i'd say their +/- 15%. i clamped the level to the bottom and top of the flange to get some readings.

stock, the difference between where the flange is and then the other side of the axle is about ~.75mm not much.

on the new arm the top difference is about 3.25mm and the bottom was 2.25mm

using other methods that were somewhat guessing somewhat trying to do legit measurements, it seemed (from looking @ the back of the bike) the outside 2 corners were good. the inside lower corner was about .2mm forward too far and the upper was around .5/.6mm too far.

took out my .5mm feeler gauge and put it the same place i had it last night. seeing there was VERY little clearance between that and the cog the driveshaft goes into on the rear diff i ground maybe 1mm off of it and put it diagonal on the inside of the upper inside bolt. 12 miles later NO CREAKING! even got out my stethascope and listened afterwards, no hints.

now i don't think its perfect but its progress! not a permanent fix but gonna do a few more miles on it.

ugh.:eusa_dance::eusa_dance::eusa_dance::eusa_dance::eusa_dance::eusa_dance::eusa_dance::eusa_dance::eusa_dance::eusa_dance::eusa_dance::eusa_dance::eusa_dance::eusa_dance:
 
Sounds good. It's interesting that the surface was changed that much. It's possible the factory tolerance was that much or the arm may have even been tweaked when we started.

Sean
 
Way to go Garrett!!:clapping:

thanks dan-o

Sounds good. It's interesting that the surface was changed that much. It's possible the factory tolerance was that much or the arm may have even been tweaked when we started.

Sean

yea i dunno. it would tend to think it had to be something after the original machining of the swingarm because mine has such little change over the length of the axle... i'll ride it a bit more tomorrow and see if i can't get some shims made up from the machine shop so i don't worry about a feeler gauge hitting the rear diff's moving parts.

not sure what the plan is from here but i can give you a call tomorrow or something.
 
Already started the replacement too.


:ummm: Sean, I'd say that was about 4-weeks, 138 posts, and 1494 views too late. Garrett has been working his butt off on this and even sent it back to you once for repair. Spurs
 
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