What's up with these forks?

[Devilman]

Hey all, any tips on IDing a set of USD forks I have that came with my bandit? Pretty sure they are oil cooled USD's but unsure exact model.

Also, They seem to have been butchered a little, any idea what's going on here?

Looks very wrong to me, but I've not played around with USD's from these models so would appreciate some help / advice

[wraith]

First of all, they are not set equal, they both need to have the same amount of lines showing on the big but part. Also the same amount of clicks on the flat head (top) 

A full pic of the forks top/bottom and length of fork top the centre spindle, and what are the dimensions of the forks at both top and bottom yokes? 

All that will help ID your forks 

[Devilman]

After doing some measuring, they appear to be 750 forks, as they're 50/54 top/bottom. Haven't had the chance to measure length though to try and figure out what year they came from.

Yeh I know they were not set quite equal, my larger concern is the right-hand fork which almost looks like it's coming apart, with the snap-ring showing.  When you adjust the screw on the top, only the brass screw itself should extend, but somehow it looks like part of the top cap assembly has failed?

[Joseph]

Fork ID number is cast inside the feet of the legs

[Devilman]

3 minutes ago, Joseph said:

Fork ID number is cast inside the feet of the legs

Inside the casting where the stanchion is pressed into? Or just the inside face (facing the wheel) of the wheel spindle end of things?

[Joseph]

Inside as in facing the brake discs surface, yep 

[Devilman]

Had a quick look but it's pretty grubby in there until I get a chance to take it apart

Did a quick measurement from center of axle to top of the fork tube, 740mm or there about, so looking at the info in the Vault, They're most likely from a 750L, but would be nice to know for sure

Been looking at the parts catalogue's trying to figure out what's happened to the right-hand fork adjuster, but not really sure I've figured anything yet 

[wraith]

Maybe a case of stripping them to find out

[Devilman]

1 minute ago, wraith said:

Maybe a case of stripping them to find out

Indeed I fear that may be the case, hence why it would be nice to be able to positively ID them to a specific model / year in case I need some parts

[Joseph]

[Devilman]

9 minutes ago, Joseph said:

Thanks for the reference pic

Aaah so is it the raised cast number on the caliper part of the bracket, or the numbers stamped into it near the spindle ?

Are they a direct link to the OE part numbers?  I've found cast numbers like that on parts before that are not anything of the part number (such as on shock linkages) ? 

Edited April 30, 2022 by Devilman

[Joseph]

S2711L (or R) is the ref type you're looking for. 

Google whatever you find and you should be able to find out.

That example i gave fits 750 90-93 i think ?

Edited April 30, 2022 by Joseph

[Devilman]

14 minutes ago, Joseph said:

S2711L (or R) is the ref type you're looking for. 

Google whatever you find and you should be able to find out.

That example i gave fits 750 90-93 i think ?

Thanks, much appreciated Looks like I have the same ones, S2711 L/R 

[TLRS]

My bet is on srad 750..

[Devilman]

15 minutes ago, TLRS said:

My bet is on srad 750..

According to the Vault, Srad were only 725-730mm in length, Mine are 740, which looks to match up with 750 90->

[TLRS]

You're right, spindle size seems more early 90ies too..

[Blue]

A pic of the bottom of the outer fork leg could tell if its early or later slingshot

[fatblokeonbandit]

easiest way to tell is the bottom of the stanchion, L/M have the seal carrier as a separate part,, the later water cooled WN onwards are all one piece, 

gold ones on right and black ones are L/M silver ones on left are water cooled 1100, silver ones in middle are WP, gold in middle are K series, different spindle size and spacing, . and the blue ones are 750 WR.. SRAD have bigger spindle size than the slingy ones but same spacing. ..

 

 

 

 

 

 

 

 

 

[Devilman]

Cheers Fbob, That helps a lot. I'll take a look in a couple hours when it's light and see if mine have the separate seal section or not.

Hopefully won't be too tricky to check, My forks were coated years ago so I guess I will see

[Devilman]

Well, looks like mine are indeed L/M 750, They have the separate seal housing

Unfortunately I seem to be discovering more and more things with concern me with this front end

With the wheel out and the forks off the bike, I've found that one of the forks seems to have slack / free-play in it, equal to the distance the on the preload adjuster? I've not messed around with USD's, is this normal / to be expected, or is something indeed wrong?

And lastly (for now lol) Is this definitely an L/M bottom yoke and is it possible to tell (visually or with measurements) if the stem is definitely a Bandit stem? The thing is rotating round and round in the bottom yoke like it's sitting in a bearing, it's bizarre. 

*edit*  Pretty sure I figured out wtf is going on with the stem... the only thing holding it in is the lower bearing race 

Edited May 2, 2022 by Devilman

[TonyGee]

somebody has seriously bodged that front end   the stem should be an interference fit. 

[Devilman]

4 minutes ago, TonyGee said:

somebody has seriously bodged that front end   the stem should be an interference fit. 

Yep, this bike had quite a list of terrible engineering decisions, fortunately I chose to rip into it before riding it

They had fitted a Banana arm but their choice for "bearing" after chopping down the pivot width, was to wrap a valve spring in alu tape and shove it into the swinger 

[fatblokeonbandit]

The pre load adjuster has probably come apart or the wrong sized spacer, or no spacer  fitted to the fork with the play..

the stem will be an early 600 one as they are sometimes 0.1 mm smaller for some unfathomable reason, and need knurling to make fit proporly, ive done it several times and it works well.. or get hold of a 1200 stem or later 600 one.

Edited May 2, 2022 by fatblokeonbandit

[Devilman]

2 minutes ago, fatblokeonbandit said:

The pre load adjuster has probably come apart or the wrong sized spacer, or no spacer  fitted to the fork with the play..

the stem will be an early 600 one as they are sometimes 0.1 mm smaller for some unfathomable reason, and need knurling to make fit proporly, ive done it several times and it works well.. or get hold of a 1200 stem or later 600 one.

Looks like I'll have to strip down and rebuild both forks then  It's a shame really, as the chrome is really good on the legs, just every other part of them isn't so pretty 

I'm tempted to drop in an '88 GSXR 750 front-end I have sitting here into it at this point.

Honestly this bike is starting to feel a bit like a lost cause / parts cannon, I picked up a B12 swinger to put in it due to the butchery that had been done to fit the banana arm, only to find the 5.5 Wheel I thought I had kicking around was actually another 4.5 

Now with needing to get a replacement removeable frame section (mine's rotten), getting the thing media blasted and powder coated and needing to source a B12 rear wheel & sprocket carrier I'm starting to think I should have just thrown a clean B6 arm in there with the wheels I have and be done with it

[fatblokeonbandit]

What steering stem is in the yoke in the 88 front end.?

and the 600 wheel can be used with a 1200 swinger with the right spacers