Couple of noob questions re. suspension customising

[magicmonkey]

So, I've just got myself a ZXR which needs some love and while pulling it to bits I've noticed that the suspension set up doesn't look like it's how it should be. I know the front forks have had the tripple clamp mounted at a lower point than where it is mounted in the manual (with the apparent affect of lowering the front) so I'll be putting them back in the right place. The rear suspension also has 3 rather thick looking washers on the top of where it bolts onto the frame (between the bolt on the top and the frame) and I'm not sure that they should be there.

I'm pretty sure that the bike has been used for racing by a previous owner but that was at least 4 years ago now and I'd like to get the suspension set back to stock so that I have a base point to play around with it frmo, at the moment there's still a lot of work to get done before I even look at the suspension but I'd like to get a decent idea of how to do things before I start attacking it with a spanner!

Anyone got hints about tell-tale signs of suspension mods which I could try and work out what's been done from?

[vifferman]

Both those mods will have the effect of increasing the apparent fork rake, amke the bike steer a little quicker. It's not likely, but if the rear shock isn't the original fitment, another model that's slightly shorter may have been fitted. (It's common f'rexample, to fit CBR9xx shocks to VFRs, but they're shorter so a spacer has to be added).

[Shaun]

Find a manual and set it all back to Standard settings and see what you think

[HenryDorsetCase]

If its suspension was set up for racing then it sounds like he has dropped the front and jacked the rear to get quicker turn-in and whatnot. Possibly too, it has hard springs and damper rates set up for the track, not the road. at road speeds its likely twitchy, very hard riding and uncomfortable.

The other point would be to service the suspension once you find out the stock settings: at least change the fork oil and stuff, maybe see if the shock can be serviced (likely not): those bits are nearly 20 years old now, most likely, so in need of TLC.

While you're at it check the wheel bearings, steering head bearings, swingarm pivot bearings, fork bushes etc....

and alignment: pointless doing all that if the two wheels arent pointing in the same direction.

[magicmonkey]

Find a manual and set it all back to Standard settings and see what you think

Yeah, that was the plan but it's a 1989 zxr 250a and I can't find a manual for one of those, just the zxr250c which is the same in pretty much every way apart from how the petrol tank and rear suspension fit, doh!!

[magicmonkey]

ok, I've found somewhere to hang the bike from while I change the suspension but I'm a bit unsure about where I should attach to the bike. My first thought is to connect to the top of the tripple clamp and raise the bike, loosesn the forks, adjust them and tighten back up. Is that pretty much the right thing to do? I'm just a bit worried that I might end up damaging the triple clamp if it's not strong enough to be load bearing ...

[quickbuck]

That will be fine....
Guess where the best place to crank your bike down on a trailer when transporting is....... Well, actually lower triple clamp,.
But, yeah, hoist it up, okay take the weight by suspending it from the top triple clamps, loosen off the Fork Retaining Screws, and slide your forks down again.
THEN, most important, TIGHTEN up your triple clamp screws to the correct torque......

Can't remember if the A model has upside downers, but this is very important.... Good practice to torque bolts anyway...
Now, I bet you don't know anybody with a torque wrench....

[magicmonkey]

That will be fine....
Guess where the best place to crank your bike down on a trailer when transporting is....... Well, actually lower triple clamp,.
But, yeah, hoist it up, okay take the weight by suspending it from the top triple clamps, loosen off the Fork Retaining Screws, and slide your forks down again.
THEN, most important, TIGHTEN up your triple clamp screws to the correct torque......

Can't remember if the A model has upside downers, but this is very important.... Good practice to torque bolts anyway...
Now, I bet you don't know anybody with a torque wrench....

heh, believe it or not, the guy I bought the bike off actually gave me a torque wrench :)

Thanks for that,not I've got a bit of confidence in the idea I've also got a plan for the weekend :D

[magicmonkey]

That will be fine....
Guess where the best place to crank your bike down on a trailer when transporting is....... Well, actually lower triple clamp,.
But, yeah, hoist it up, okay take the weight by suspending it from the top triple clamps, loosen off the Fork Retaining Screws, and slide your forks down again.
THEN, most important, TIGHTEN up your triple clamp screws to the correct torque......

Can't remember if the A model has upside downers, but this is very important.... Good practice to torque bolts anyway...
Now, I bet you don't know anybody with a torque wrench....

heh, believe it or not, the guy I bought the bike off actually gave me a torque wrench :)

Thanks for that,not I've got a bit of confidence in the idea I've also got a plan for the weekend :D

[quickbuck]

heh, believe it or not, the guy I bought the bike off actually gave me a torque wrench :)


What a great guy.....

[magicmonkey]

What a great guy.....

yup, he was a pretty decent guy :)

[sinfull]

What a great guy..... Would give me confidence in the work the guy has done to the bike lol apart from the wickedly quick turn in !

[quickbuck]

Would give me confidence in the work the guy has done to the bike lol apart from the wickedly quick turn in !
Well, yes.
It does change the picture a little...

The Wickedly fast Turn In, is really a bit of a personal thing though.... So, I'm picking he was not exactly a learner....

[magicmonkey]

Unfortunately it wasn't him who did the work, it was a mate of his who was either going to, or did, use it for racing. The guy I bought it off definately liked his motors but he claims to not know much about mechanics. Apparently the torque wrench was something he bought and used once or twice before taking up permenant residency on a shelf. Still, bloody nice of him to let me have it as I now own a torque wrench and an impact driver, there's no job I can't do!! (watch this space for some word eating!)

[pritch]

I now own a torque wrench and an impact driver, there's no job I can't do!!

All you need now is a can of CRC. :yes:

Actually I have a torque wrench as well. Way back when I bought it the manufacturer claimed it was standard equipment throughout the British car industry. For some reason I find that worrying rather than reassuring...

[vifferman]

All you need now is a can of CRC. :yes:


Not.
CRC is useless apart from for cleaning tar off (and even then, there's better things). Buy some WD40 instead. :yes:

[magicmonkey]

I've got loads of CRC at the moment although I've found that a combination of kerosene, steel wool and autosol have been getting a nice finish on even the most nasty areas, it's just about impossible to get in the nooks and crannies though!

[avgas]

Swingarm still standard?
Old ZXR4 I had actually had a later ZXR7 swinger with shock as it was better kit (banana rather than straight etc).

[magicmonkey]

Swingarm still standard?
Old ZXR4 I had actually had a later ZXR7 swinger with shock as it was better kit (banana rather than straight etc).

Looks like it is, as far as I can tell anyway, my manual is from a 'c' model so I can't be sure (the 'a' model ones are in japanese and I can't even find one of them for the pictures!) I was going to spend a bit of time in the garage yesterday and post some pics of the rear suspension to ask opinions but following an unexpectedly heavy Saturday night I decided to spend the day watching crap on tv whilst groaning instead, hopefully I'll have a bit of time for it tonight...

[magicmonkey]

ok, so I've worked out how I'm going to sort out the front suspension but I'm still a bit stumped on the rear. On searching the interwebs I've found this picture:

http://www.dirtygirlmotorracing.com/zxr/teardown-suspension-rearview.gif

which shows the spacers exactly how they are on mine, could anyone tell me if this is just 2 different people employing the same mod or if it's standard to have those spacers there?

[avgas]

ok, so I've worked out how I'm going to sort out the front suspension but I'm still a bit stumped on the rear. On searching the interwebs I've found this picture:

http://www.dirtygirlmotorracing.com/zxr/teardown-suspension-rearview.gif

which shows the spacers exactly how they are on mine, could anyone tell me if this is just 2 different people employing the same mod or if it's standard to have those spacers there?
Sorry for sounding a bit like a blind noob here - but I think my perspective could be a bit different to yours.
When you were saying spacers I was thinking around the linkages to hold the shock in place. But could your draw a circle around what you mean in the photo?
Cheers
Stew

[magicmonkey]

Sorry for sounding a bit like a blind noob here - but I think my perspective could be a bit different to yours.
When you were saying spacers I was thinking around the linkages to hold the shock in place. But could your draw a circle around what you mean in the photo?
Cheers
Stew

I'd love to, just haven't got any image editing software at the moment (fresh install, being lazy!) I mean the bit right at the top, above the frame, with the 2 bolts and the 3 washers on it. Looking at how it goes together I can't see that it makes a difference to the suspension set up, it just makes getting the airbox out a pain in the tits!

Other than that, I strapped the bike up and got the front suspension to the right height earlier so that's all good :) a bit of 'percussive persuading' helped out a treat :D