Dilemma

[Swesty]

Having recently bought this http://www.ukgser.com/forums/showthread.php?t=347128 , i'm sure you'll all recall it. I'm faced with the dilemma of what to do with the front end. There appears to be an inordinate amount of 'sticktion' (feel free to correct my spelling of an unrecognised word) on these IIRC R90 forks. No do I try to source a right leg which will allow me to improve the braking? then sort out the sticking or source something 'jap' that'll do the job better? Bearing in mind money has been spent on a 21" front wheel. I have a set of airhead forks with Brembo calipers which would be nice but I have the wrong wheel to suit.

Thoughts, offers of spares, help..........

Cheers

 

[Kenny]

IIRC to put a second disc on the spoked wheel, you will need two 'shallow' discs ( ie the six bolt disc mount is probably a deep version on your bike and to stop the callipers hitting the spokes, then shallow disc mounts are required.

Re forks....hard to say what is causing the stiction without a complete strip down ( they are a doddle to work on but the likes of Scrimminger would set them up properly - £££ ) or ask what the last owner changed on the forks ( maybe even to big a top spacer etc ). If not and they are worn...then £££ will need investing in her

 

[Wrigsby1]

One of the obvious bits to limit the stiction is new fork springs... I bought a 70k 90's R80RT and the springs were crap... they had sagged a fair bit and felt like they hardly moved over bumps... At a standstill there was hardly any return... Progressive springs from Motor Works/Bins and there was 200mm travel rather than 150mm and a smooth action... Obviously the fork oil weight is up to you...

 

[Rob Farmer]

The ate forks work really well when they are overhauled.

I sold those forks to bigyellags, they had done around 105k and were swapped for a twin disc rs setup.

There's a rubber buffer in the bottom of each fork leg that breaks up clogging the damper mechanism up. If you wash the legs and dampers out, fit new damper rings and a proper 5w fork oil instead of the crap aero shell that motobins sell I'm sure you'll end up with a decent front end.

 

[Swesty]

Bits ordered, thanks chaps. Is there anything specific to these I need to know whilst stripping them out? Hidden circlips? Any really expensive tools required? or just a seal removal tool, vice and a big hammer.

 

[Rob Farmer]

You may want to buy a cheapo set of feeler gauges to sacrifice when fitting the damper piston rings back in. Flushing everything through and making sure the ball bearings in the damper mechanism are seated properly and not rusted is important.

If you have access to a lathe then the piston ring slot could be enlarged to take an additional three rings on each side.

I went to hell and back trying to sort the forks out on my old r100rs, I've never had a front end out so many times on a bike before, turned out to be the aero shell oil from motobins causing the strict ion. Swapped it for belray 5 and the problem went away.

You prolly haven't noticed but your bikes fitted with a 90/6 bevel box. I cocked up big time, fitted my 100rs bevel box to the 90/6, sold the 90/6 bevel to bigyellags and ended up with a standard 37/11 for my RS. It cost me more to replace the RS bevel box than I sold all the parts for that are on your bike

 

[Swesty]

That was easy, didn't get around to machining the slot out for a double set of rings though. Also bought a RHS fork leg so I can do a twin disk conversion. While at it I've bought a set of progressive springs and was a little alarmed to find thier length different whilst rebuilding. So just to check I offered it against the originals. Now I was expecting a little sag, but what I found was a little disturbing. All 3 of the used springs were different by up to 35mm, neither matched the progressive ones. I'm not bothered as all appears ok now. Rattle can paint job on the tank and a set of reverse cone mega's. It's coming round to how I want it. Cheers for the advice

 

[Rob Farmer]

The RS/rt springs are considerably shorter than the standard springs. Sounds like you have a mix of springs.