168 replies to this topic

[dandywarhol]

The eye witness, (now a suspect), said: " I only had to whack her 4-5 times before she come off. But, I had her good & lubed up for quite a while before then, & I could see it was working almost from the start. After I got her off, well, ah, I could see she looked pretty dirty down in there. No surprise I guess"

Suddenly thought I was on the wrong forum for a moment.........................................

[dapleb]

I was determined to make sure the rebound adjuster (flat head screw on top of shock bolt) was not seized as they were on my existing forks....of course I forgot...and of course they ARE seized. So its worth checking that the adjuster is not seized whilst the cap is off!!!!

[Tom S]

!¿!£@#§$%() and !&¢*¤¿?!! FORKIN FORKS!!
Finally got all the parts. Everything going OK. Now I can not get the stinkin dust seal in.
No one said anything about this & I did not expect to have any problems with it either. Made up some solid drivers for the oil seal & dust seal. I have about beat this thing to death. Was convinced that I had put something in wrong. But it all looks right. Even tried the old dust seal. No go. If I pull the wire clip that sits just above the oil seal it does go in further, & I am sure it would go all the way if I used the driver instead of just tapping around the sides with a wood dowel & hammer. The oil seal went in fairly easy. I pounded it down several times again after the dust seal would not go. It must be all the way in & measures to be just the distance that the dust seal needs to set.
Wish I had measured how far down into the slider the oil seal was before taking it out. Because now I am not so sure, as it almost looks like it does not set as deep as I remember. Also don't know if there was a second groove that the wire clip might set into, only higher up.
I don't think so, but when things are not working right you start having doubts.

At this point I am ready to just leave the stupid little wire clip out. Those seals ain't goin nowhere.

Any idea what I am doing wrong?

One other question. In this post:
http://www.carpe-tdm...&...post&p=6164
SteveGlover says:
"If the spring has somes coils closer wound at one end (I don't think the 850 has this) then these go at the top."
Hmm-, mine came off the other way 'round. Closer coils at bottom. Manual says nothing, of course.
Pretty sure I did not mix that up. ??
In fact, if, as I suspect, Stink-Foot has this laid out in order, the closer wound coils are at bottom.
His pic:
http://www.students....er_assembly.jpg

I can almost see from my own pic that the coils are wider on top.


Yeah, looking at the spring now, I see that I would be looking at one more coil if the tight wound end was on top.
So, I guess that is not a question, let's call it information.

Not to say that SteveGlover's write up was nothing less than excellent. Helped me. Thanks Steve, wherever you are.
Sometimes things come out ¿?

I have been taking pix of all this & will try to give a full report. There are some differences between what the factory manual says & some of the things that I have read here that agree with the manual & what I am finding. I hope to pass that info on if it will help someone else.
Sometimes it kind of sucks that I seem to have the only TDM for thousands of miles around.

I gotta get this thing on the road as my Buell rear tyre is smoked & new ones are a week out. Dammed if I am takin a car.

I say again:
!¿!£@#§$%() and !&¢*¤¿?!! FORKIN FORKS!!
Anxious in Anchorage, a Professional Crastinator that did not order tyres soon enough.

[dapleb]

Hmmm is the groove for the retaining ring totally clean? wonder if that is partially blocking the dist boot. I too made a pipe drift to slot over the tube and use as a drift. I lubed the dist seal and it just plopped straight in (didnt need the drift at all)!

My springs came out (and went back in) tight coils to the top. The illustrations in Haynes show this too.....mind you neither of those points make it the right way!

Cheers
dapleb
p.s. ever get that feeling you should be somewhere else.....hnag on....RTT ....arggggggggggghhhhhhhhhhhhhhhh....BOOOP

[Tom S]

Everything is very clean Dap. I don't get it. Came out easy.
For now another note penciled in the manual to show tight coils down.
I have some Haynes manuals for cars. They do suck. Can't you guys get better or factory (also sucks, but got to be better than Haynes) ones?
Are they just too costly?

[Tom S]

I am still trying to remember why the spring even cares if it is up or down. I think there is a reason but dammed if I can remember what/why. Maybe I should search for progressive springs. Not making sense now. You push on the spring, get same reaction either way as far as I can see.

But don't care. I'll search later. Just need to get dust seal in, that is the real dilemma. WTF?!
Yes, I should be somewhere else. The garage! I am going there--

[dandywarhol]

I am still trying to remember why the spring even cares if it is up or down. I think there is a reason but dammed if I can remember what/why. Maybe I should search for progressive springs. Not making sense now. You push on the spring, get same reaction either way as far as I can see.

But don't care. I'll search later. Just need to get dust seal in, that is the real dilemma. WTF?!
Yes, I should be somewhere else. The garage! I am going there--

With engine valve springs the close coils always go to the part which isn't moving i.e. the cylinder head.
so I guess then that the forks will have the close coils to the top

[Tom S]

Ok, here is the deal.
I put on my even stronger close up reading glasses. Hate that. Poked around in there some more. The place where the wire retaining clip was seating did not look deep enough for that clip. I pried the dust seal up off the left fork that is still on the bike. Was afraid to do that before as I wondered if I could get it back on. The oil seal did indeed look as deep down in there as I recalled. Deeper than the right fork that I am working on. And the retaining clip did not protrude into the area where the dust seal seats.
The top of the oil seal is 1/4" or 6.35mm below the top of the slider. The top of the oil seal on the right fork is higher.
Slightly more than 1/32" or 0.7950+ mm. Maybe 1.19mm. Whatever.
There is a 'false lip' near top of slider that the clip sat in. Right on top of the too high seal. Where you would expect a retaining clip to be.

I am disgusted. Still can not figure out why oil seal sits to high. I have pounded it down several times.
The washer below the seal is a flat washer.
WTF?
Oh, yeah, I should not have been afraid. I pushed the dust seal back on easily with my fingers. As I would expect to.

[stevepsd]

Tom,

Did you measure the height of the new oil seal vs. the old ones (it should also be embossed on the seal, a series of 3 numbers, that give the seal OD, ID & height in mm).

Also teh stock springs are progressive rate units. The tighter wound coils are at the top. Sounds like yours were installed backwards at some point. The parts manual show the correct origentation, but the factory & Haynes manuals are, well......pretty crappy; not at all like the Honda MC service manuals (at least during the 1980's).

Just a note, when replacing the fork fluid, don't rely on the amount of oil to use states in the manual to be correct, use the measurement menthod (tubes collapsed, no springs installed, measure from the top of the fork tube to the oil). My forks had a noticable difference in volume - putting in the same amount of oil into both forks, the fluid level was different by almost 1" !! That is a huge difference and will really affect the overall suspension rate - due to difference in the air column in the fork.

Hope this helps.

-steve

[Tom S]

Thanks Steve.
I did not measure the old vs new seal other than to hold them & set them together. They were the same. Or so I thought. Would have also thought that I could see or feel the diff of aprox 1/32"=.0313"= 0.79502mm. Now not so sure. Can't really tell much diff now when I put them on the counter together.

I have been using the old seal to install the new one. Sanded off most of the rubber on old one so it would not stick into the slider. Then sanded off all of the outside rubber when things did got go right. So the numbers are gone along with the top & bottom side of the rubber (neoprene is to hard to spell) Therefore old one is not as thick as it used to be. New seal, the other new seal, that is indeed same as the one I installed is 10.78mm thick. Old one is 10mm ± with most all the rubber gone. Just the additional distance that I need to get the dust seal in. Hmm--?

Numbers on new seal = BR4642E NOK 3. Fork upper is 40.89mm dia. So those #'s do not seem to relate.
I can see the last letters left on the old seal, MM. Nothing like that on the new seal.
New seal part # is 3GM-23145-AO

Interesting about the spring. Yeah, I know they are progressive. Tight on top somehow makes sense. Maybe someone has been in here before.

Yes, thanks Steve , I have read that here & will be measuring the oil level. My book says 165 mm, or 6.5".
BUT--
This post says:
http://www.carpe-tdm...&...post&p=6882
Just for completeness, here's the fork oil levels for the various models of TDM's:
Model, Year, Volume, Level
TDM850, 91-95, 395cc, 151mm
TDM850, 96-on, 515cc, 130mm
TDM900, 02-03, 507cc, 133mm
TDM900, 04-??, 545cc, 127mm

Mine is a '92. More conflicting info. Steenking book! Maybe I'll split the difference, 158 mm. ??
But have read here that lowering it by 10mm was better. 141mm? !55mm? WTF?!
Just talked to Yammie shop. No real help. Part # has been superseded 3 times. Part I have is the second.

I think I will try pounding that seal down one more time after taking careful measurements before then after. I think it is all the way down. If it don't move I am going to leave out the clip & even trim the bottom of the dust seal a tiny bit.
Nothing to lose at this point, It should work & I have parts on order for the other side.

Anybody got known correct old/new seal handy to measure the thickness? Different part #?

Attached Files

•  seal_tag.jpg   27.72KB   9 downloads

Edited by Tom S, 30 June 2006 - 11:45 pm.

[stevepsd]

Tom,

My parts list, current as of just a year or so ago, shows the fork seal as part # 3VD-23145-00-00. 3VD is the Yamaha model number for a TDM; 23145 is a fork seal. Your seal # 3GM-23145 is for a 1990 FZR1000. Did the seal get superceeded from the 3VD to a 3GM to a 3LC by chance? I'll check with my dealer tomorrow to make sure you have the correct seal. It should not be this much of a problem to put in a darn fork seal. And yes, you should be able to feel a difference in thickness between the two, especially side by side.

Is the bush that is in the fork tube fully seated? If I remember correctly, the bush goes into the fork leg, then a thin metal washer goes over that, then the fork seal. Kind of hard to see with the fork tube in the way, but I believe it's possible that if the bush is not fully seated then everything else would be to 'high'...or not...can't remember clearly. But I'd double check.

As for fluid level, I used 165mm/6.5", if you want it a bit more compliant, go to 7".

Hope this helps some, and let me know what you find.

-steve

[dandywarhol]

Dappers not the happiest of bunnies at the mo.......he's just blown a fork seal and we're off to Greece tomorrow

Going via Mr G's place to raid his ol' Mk1 of it's forks on Wednesday.......................................

[unclesumo]

Did yer fix yer pump & blow the wrong end up by any chance?

Was good meeting up with you again at the RTT. Have a good trip

[dandywarhol]

Did yer fix yer pump & blow the wrong end up by any chance?

Was good meeting up with you again at the RTT. Have a good trip

lol unc..............fixed the pump and got Dappers arse end pumped up (f'nar, f'nar).............off for the ferry this afternoon and pirate G's forks while he's still here in th eUK..........

[wicklamulla]

lol dodgy GPS's, fournales pumps, fournales shocks, blown fork seals.......... s'never ending !

[wicklamulla]

Aye I bet they just "camp" on Guinness' lawn for 5 weeks trying to get the bikes and the gps going right.

goin round in circles more loikes..............

[dapleb]

lol dodgy GPS's, fournales pumps, fournales shocks, blown fork seals.......... s'never ending !

Yeah not a good few days for my suspension. Not sure why fork seal suddenly failed afer a good few hundred miles of being fine.

Swapped to G's forks no probs, both bikes propped with rods through the front of engine (made by the wee mans engineering mate in Edinburgh)! .....there was a slight weep from one of G's forks too.....which is now pishing as much as the one I took off....should be fine only a few thousand miles to go...just dont tell him.....ok

Cheers
dapleb

[wicklamulla]

lol you and seals just don't see eye to eye !

[Tom S]

TDM Fork seals & bushings.
Have not been able to get on the site since the end of June, so could not tell you what happened & how I screwed up.
It is all good now. Back together 7-1-06 I'll try to pick up where I left off. Owe it.
Some of this has already been covered, sort of a recap. Including some do's & some DON'T DO THIS!

'92 TDM 850 (Yamaha sticker on headstock says11/91)

Just loosened the cap here.


Pulled fork apart. As warned above, the teflon on the bushings did get buggered. Lower bush.


Upper bush.


Dump/ pump out old oil, remove bolt at bottom of fork & pull out damper.
The cup that sits below the damper did not have the D-shape or squared off hole to match bottom of damper, just round. Not damaged in any way, must have been made that way.


Things seemed to be going OK.
Pumped out all the old oil & stuck lower damper in some gasoline (petrol) & pumped more to clean it out. Did this a couple times, until it was clean. 1st go. Dirty.


I had two of these

But only 1 new set of new bushings. Later to be a source of concern.

Sanded some of the 'rubber' off the old seal as I was going to use it to drive the new one in. They are in there tight & I did not want it to stick. As you will see, I sanded it all off before I was done. Not necessary.


*******************************************************
TIP!
Loosen fork cap before even removing fork. It is already clamped in there nicely. Stuck mine back in & lightly chinched the top tree.
Easiest way to hold it. Oh, I never had to remove any of the fairing like the manual says either.
A 15/16" deep socket fit the cap much better/tighter than the 24mm box end. Bunged up flats from 24mm. Fixed them.
Spring pre-load is backed off in pic, short socket fits if it is not. (I now learn)

*********************************************************
Lubed up the seal & even warmed up the top of the sliders & drove it right in.
The just right size piece of pipe, 1&7/8"/ 47.625mm I.D. 2.5 ft long was the one I had. Wood block on top of pipe to pound on.

BUT!- Put fork cap in, just using fingers, into open top of fork to keep out dirt from the pipe or block.
DON'T! do like I did, put in a rag, a paper towel. Came out every time I removed pipe to check progress. Forgot to replace it once.

Seal went in ok. But I thought it sat a bit deeper than that. Hmm? Put in wire clip. Put in 300cc of 10W BelRay.

Oh, maybe I should slide in that dust seal.

Damn, won't go all the way down.
All manner of suspicions arise.
Troubles begin.

Build a new driver, beat hell out of dust seal with clip both in & out. Goes in farther with clip out, looked like it should. Still--

I knew I'd done something wrong.

Was talking to Stevepsd via e-mail when I couldn't get on Carpe TDM. He looked up parts & talked to his dealer too.
Some of what I told him, minor edits.
Maybe this will help to explain. I hate typing. This took 2 days to put together, with pix, from memory. Ugh.
*********************************************************************
Steve-
I did not have the top bush seated. Totally blew that , paid it no attention at all. I just pulled it back apart. When I went to work on it tonight, the fork oil that I had prematurely put in before installing the dust seal was already leaking!!
I pulled the 2 pieces apart just holding them in my hands! I feel stupid now. The bushes did not get damaged (surprise!) & I had another seal.
(Tom, acting like he ain't turned wrenches for 48 years or so. DAMN!)

I properly seated the upper bush & everything went very smooth after that. Pushed in the dust seal with my fingers, as it should be.
I can't believe I made such a dumb mistake.

Here is a pic of what I used for a bush driver.
L-R, old bush to drive in new one, 1st old seal with rubber sanded off so it wouldn't stick, 2nd old/brand new seal that I ruined because bush was not in place, 1st cardboard t-p tube to protect fork, with another, longer, cardboard tube above it. Used a 2.5' long piece of pipe that was just the right diameter to push the seals.
( I wonder what the Brits call tp, toilet paper, WC paper?) ( :


That bush did not go in quite as easily as I thought it would either. It went in OK but being a split thing one side was at first just a tiny bit higher than the other. Fractions of mm.
If you just eyeballed it, it looked fine. But I wanted to make sure that it was in there totally square & checked with mic several times & kept tapping it down. Took a long time before I was satisfied.

By the time I was done I could not even find the split in the bush. New seal went right in using the same drivers.
I will save all the old parts for further use/tools & reference. I never throw anything away.

As it turned out it was a good thing that I had sort of goofed by putting in the 1st 300cc of oil before installing the dust seal.
(I use a baby bottle that I bought 30+ years ago just for measuring fork oil. It is marked in ounces & CC's.)
After sitting overnight there was oil above the oil seal. Oil seal died trying to drive in the bush that I thought was already home.
That was a downer for sure.
Thought I was really screwed as I have yet to get the second set of bushings.
Was sure surprised when the fork came apart without any damage to the bushings. So, since I did have another new oil seal I could still go on with it.
I started by measuring everything with my nice digital caliper. Yup, it should all fit. And it does.
But it would have been much worse had I just assumed that the oil seal was to thick & went ahead with my plan to leave out the retaining clip & put in the dust seal, & reinstall the fork. That was just wrong & I knew it. Maybe I would not have known until the fork was back on the bike and spewing fork oil all over the place before it even left the garage.

*************************************
ANOTHER TIP! -- before I forget--
Do not bolt fender down before installing wheel.
I put wheel on, then tried to replace fender. Oops, no way.
Removed wheel & bolted fender down tight. Could not get axle in to left fork. Big struggle.
Remove wheel & see that forks are turned & no way is axle going in. WTF?
Fork lowers held in place by fender bolts that have enough slack in the holes to cause lots of mis-alignment.
Recommend just putting fender in place & leave bolts laying on the floor for the time being. That way you don't forget to put them in & tighten them, after the wheel is on.
****************************
Added lots of notes to manual as I went. Set oil level per manual, @ 6.5", 165mm from top of fork.
Installed spring with tight wound coils up. The reason why came back to me.
Good to go.

Simple stuff will kill ya sometimes. Well, if you want to get right down to it, everytime.

All peeps in this thread have provided good info & links on this little job. I thank you.
Had I not known about the teflon on the bushings getting ruined when taking the forks apart, I would have been down for another 10 days ± waiting for parts.
Parts/service guy did not think I would need them, tried to save me money. I bit & had to order & wait for more parts after what I read here. They were not that spendy after all. Book says use new. Book was right.

Nice write-up by Steve Glover too.
http://www.carpe-tdm...o...

Could this recap qualify be added to the Depository? Added below in the thread linked just above? Maybe a link to this thread?
Maybe I can edit out the off topic stuff I posted at some later date, (read, dead of winter), so it sticks to the subject. Post as a new thread. ??
That is a definate maybe. ; )

Might save someone doing it for the 1st time on an older TDM some trouble. Has pix that may help.
The Westernmost outpost thanks you all.