Some questions about the pumpkin

[RempageR1]

Hi,

Last weekend, I noticed my real wheel was making creaking noises:
www.youtube.com/watch?v=vpoa_rN1Db4

It used to do that before, but I fixed that by tightening the loose nut number 16:

However, the nut was still tight but the noise has returned, worse then before.

When I investigated the pumpkin, I noticed I could move the coupling (number 14) up and down a little and that to me can't be good.

After the pumpkin was disassembled, I found out there`s a lot of free play when only having the needle bearing in (7) and not the other (10):
www.youtube.com/watch?v=UvENskoDayk

I assume this is way too much?

Also, I found some markings on the cogs mating surfaces:

Is this an issue?


Next, the big bearing. Looks ok but makes a little noise. Should it be replaced?
www.youtube.com/watch?v=Skkbx5qCcmg


Thanks!

 

[tugla]

Sean will be best to give advise here...

 

[gamorg02]

make sure you have the pumpkin aligned correctly first. unknown about freeplay but it can creak like hell if you don't have it lined up right. to do so put the axle through to tighten down the 4 acorn bolts then put the wheel on.

 

[wildweasel_pt]

The pinion shouldn't have that freeplay. It seems you have run it for a long time with the top bolt undone... The acceleration and deceleration can cause eccentric movement of the input shaft ruining the bearing or the case, and if the bearing is acting up with noises that might well be the culprit. I'd get another final drive, easier and cheaper than replacing those parts...

 

[dannymax]

The bearing in my '96 has a similar aound, maybe not quite as loud tho.

If I may hijack for a second....can anyone tell me which way seal (#33) is supposed to face? I installed it with the spring facing inboard toward the ring gear.

 

[tugla]

Makes sense to me Dan......but was it leaking out by axel bolt.....then might go other way but think you got it......what did you use to drive it home with....

 

[PATMAX]

Yeah that pinion is moving waay to much. I would guess bearing but without seeing it, case may be wallowed out but the bearing is the sacrificial part. That bearing isn't so bad to get to but the others?, take Weasels advice and score a good used pumpkin.

 

[twistedmax]

Yeah that pinion is moving waay to much. I would guess bearing but without seeing it, case may be wallowed out but the bearing is the sacrificial part. That bearing isn't so bad to get to but the others?, take Weasels advice and score a good used pumpkin.

I got one for sale !

 

[dannymax]

Makes sense to me Dan......but was it leaking out by axel bolt.....then might go other way but think you got it......why did you use to drive it home with....

Will take hi-jack to email. :biglaugh:

 

[[email protected]]

Seems like excessive play. Does the bearing fit tight in the case? It will come out with a blind bearing puller but should be tight in there.

As noted, you may be further ahead to just replace with a used unit. Bearings and seals add up quickly.

Dan, That seal goes in with the spring facing the ring gear as you noted. At least, that how mine was from the factory and how my new one was installed.

 

[dannymax]

Seems like excessive play. Does the bearing fit tight in the case? It will come out with a blind bearing puller but should be tight in there.

As noted, you may be further ahead to just replace with a used unit. Bearings and seals add up quickly.

Dan, That seal goes in with the spring facing the ring gear as you noted. At least, that how mine was from the factory and how my new one was installed.

Thanks Mike! I could find nothing on that in either Clymers or Haynes....they don't address the inside of the FD at all....that I could find.

 

[[email protected]]

Thanks Mike! I could find nothing on that in either Clymers or Haynes....they don't address the inside of the FD at all....that I could find.

Its been awhile since I've been in there. I was second guessing myself. See the attachment from the Yomamma manual.

 

[RempageR1]

Hi,

Today, I continued fiddling with the pumpkin and found out some interesting stuff.

First, without the small axle in, it still creaks. So the freeplay was not the cause. The axle itself has no markings and no wear you can feel with your hand so it should be all right. The needle bearing itself is still snug in the housing, so the housing should also be fine. When I got the bike, the nut was already loose (I found out a couple of months later), no clue how many miles it has been like that....
Next, I removed all shielding around the wheel and pumpkin like so:

When I put my finger in there, I can feel the middle section being pulled out of the rubber and then snapping back in place again, so basically moving up and down when I rotate the wheel. So something is bent. Next, I checked the axle as it`s the first thing that came to mind:

And now rotated 180 degrees:

So yes, it`s bent

I`ll go ahead and replace the bearings of the small axle as they do not cost a fortune and off course replace the axle. Then I should be good to go. I`ll update as soon as I have some news.

Thanks all for help so far!

 

[twistedmax]

Cool , easy and cheap. Good luck

 

[dannymax]

Its been awhile since I've been in there. I was second guessing myself. See the attachment from the Yomamma manual.

Cool....validation! Thanks again Mike! :worthy:

 

[wildweasel_pt]

Even if the axle is bent (not much) It shouldn't creak intermittently as the wheel bearings may be getting partial side pressure that will happen all the time as the axle is solid in place. The wheel makes the outer races to be perfectly parallel but the inner races may be converging due the bent axle, thus the side pressure on bearings i was talking about, all and all that may cause freeplay on bearings with time but no intermittent creak... if you know what i mean, unless you have cracked ball bearings or debris inside the bearings.

 

[RempageR1]

Even if the axle is bent (not much) It shouldn't creak intermittently as the wheel bearings may be getting partial side pressure that will happen all the time as the axle is solid in place. The wheel makes the outer races to be perfectly parallel but the inner races may be converging due the bent axle, thus the side pressure on bearings i was talking about, all and all that may cause freeplay on bearings with time but no intermittent creak... if you know what i mean, unless you have cracked ball bearings or debris inside the bearings.

Since the inner and outer spines are not perfectly aligned (due to the bent axle), even when engaged, their angle shifts a little with every rotation and they are forced to slide into each other a bit deeper with every turn. I have to rotate the wheel about four turns in one direction before the inner races (wheel) are pulled out far enough off the rubber bushes for them to snap back.
I`ve checked the wheel bearings by installing the axle and some pipe instead of the pumpkin and no noise then.
To me, it seems the bent axle is the culprit. It`s an easy replacement instead of finding a new pumpkin (and not knowing it`s internal state, having to paint it again etc).

I`ll let you know how it went.

 

[wildweasel_pt]

yeah, you can find an axle for 10 bucks or so. If the axle is like that i'd check the rear wheel for straightness

 

[dannymax]

yeah, you can find an axle for 10 bucks or so. If the axle is like that i'd check the rear wheel for straightness

+1 Pretty hard to bend an axle without bending something else too.

 

[RempageR1]

yeah, you can find an axle for 10 bucks or so. If the axle is like that i'd check the rear wheel for straightness

_this_ wheel is straight, I`ve checked but this is not the wheel the bike came with.... Since it`s an 85-er, no clue what has happened in it`s past. What I do know it`s had a hard life with previous 'mechanics' working on it.

I`ll keep you updated!