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hmurphy
21st September 2011, 16:49
Hey what have people done to replace springs in shocks for their buckets? I have seen a few buckets with R6 or GSXR600 or ZX6R shocks and I'm just wondering what people have done about them considering they are over sprung for light weight buckets and the low forces we put into them around kart tracks. I can get a new spring made from scratch for $140 plus GST. This is one option.

This is not for my bucket, it's for a mates bucket who has a GSXR600 shock. It is far too hard even on the softest preload setting.

Cheers

nzspokes
21st September 2011, 16:50
Tell him to eat more pies and it will be fine.

F5 Dave
21st September 2011, 17:29
First off when anyone says that my spider sense tingles. I'd ensure 1 that the compression or rebound is not wound in fully, either can make them miserable. check preload while at it.

Then chock the bike up & check for freeplay at the rear wheel. then pull out the shock & check for ease of movement of sw & of linkages. once sure bearings are not mullered it is worth carrying on.

RT at CKT will be able to sort out a new spring for sure. Spring made at NZ springs is an option, but can't cover all bases due to high grade spring steel often required.

hmurphy
21st September 2011, 17:56
Yeah the shock is almost brand spankin' and the damping settings have been tested on their hardest and softest settings. You can tell the differences in compression and rebound damping settings but because there is bugger all travel capable it does make it a little hard to tell (this is simply by bouncing the bike). I rode the bike round Kaitoke and with everything turned down to the softest setting, the bike was painful to ride. It would chatter/vibrate and bounce over the bumps like you wouldn't believe and tried to spit me off while attempting to even slightly push. It was like having no rear suspension.

The wheel might have some free play (can't check this right now) but unlikely as bearings are new. The linkages could potentially be an issue, they did look and seem a little crusty from memory. The shock bearings should be great (and from memory they are) because the shock has almost never been used. Will check over the list of things you mentioned.

I know Fish has a ZX6R shock in his bike and I was meant to ask him what he did to get it to work properly. If you're reading this Fish... what did you do?

The stock shock provides a much better ride at the moment but isn't adjustable and that's what Steve wants.

Deano
21st September 2011, 18:01
Would a stock SV650 spring be any good ? I'm pretty sure that stock SV's are undersprung compared with a sports bike.

Yow Ling
21st September 2011, 18:44
i had a spring made $160 at Chamberlain Springs in Chch.
What sort of bike? A r6 shock on ebay is about $15.00 thats what we put in Buddhas TZR frame with just a little exrta preload. a dead fxr shock spring maybe

hmurphy
21st September 2011, 18:53
Cheers Deano, I measured the SV spring on my Mum's bike and unfortunately it wont work on this shock. It's too long.

This is for an RGV250 frame. The shock was real cheap off ebay so I guess extra money could be spent on getting a new spring made.

koba
21st September 2011, 19:24
Cheers Deano, I measured the SV spring on my Mum's bike and unfortunately it wont work on this shock. It's too long.

This is for an RGV250 frame. The shock was real cheap off ebay so I guess extra money could be spent on getting a new spring made.

Can you use the RGV spring?

Maybe try it wit the damping set somewhere in the middle? (just a hunch)

hmurphy
21st September 2011, 19:38
Yeah we looked at doing that but the spring wont fit around the outside of the shock, the inner diameter is too narrow on the stock shocks spring. Yeah we played with a few of the settings and none are very good, the spring doesn't let it travel enough

Buckets4Me
21st September 2011, 20:27
The shock was real cheap off ebay so I guess the old owner ate to many pies


fixed that statment for you

Tz is using a gsxr600 (1998) shock in his fzr250 frame with the old fzr spring :woohoo:

maby an old fzr spring

koba
21st September 2011, 20:58
Yeah we looked at doing that but the spring wont fit around the outside of the shock, the inner diameter is too narrow on the stock shocks spring. Yeah we played with a few of the settings and none are very good, the spring doesn't let it travel enough

Another factor to consider is different linkage actions...

Ned Kelly
21st September 2011, 21:18
This is not for my bucket, it's for a mates bucket who has a GSXR600 shock. It is far too hard even on the softest preload setting. Cheers

TZ350 uses a FZR250 chassis for his Bucket and has a GSXR600 (08-09 I think) rear shock with the original lighter FZR250 spring, works OK. Earlier years of 600 have longer fatter shock bodies.

fi5hy
21st September 2011, 22:40
lighter spring and money for valving

F5 Dave
22nd September 2011, 11:20
I'd totally misread that as not for a bucket.

Will be valved for a 200kg (yes really) bike with a different linkage ratio. the 'adjustment' won't be in the area you want -or the right ballpark.

hmurphy
22nd September 2011, 11:45
Sweet thanks Fish, getting onto that.

Yeah it's got high speed and low speed damping settings (which I have never played with on a big bike... or any bike for that matter) and I have read up about how that all works. I doubted that the shock would be usefully adjustable at the low speed damping settings (let alone high speed damping settings) simply because a 100kg bucket, averaging a speed of 65km/h around tight corners and only putting out roughly 12 or 15hp at the wheel would put enough forces through the shock to get the damping valves working. I'll see how hard and how expensive this all is and let you guys know for future reference. Even I'm interested for my own bucket (but I don't really need it so I wont be silly and buy one until mine stops working someday).

Cheers for the help guys

White trash
22nd September 2011, 12:18
Sweet thanks Fish, getting onto that.

Yeah it's got high speed and low speed damping settings (which I have never played with on a big bike... or any bike for that matter) and I have read up about how that all works. I doubted that the shock would be usefully adjustable at the low speed damping settings (let alone high speed damping settings) simply because a 100kg bucket, averaging a speed of 65km/h around tight corners and only putting out roughly 12 or 15hp at the wheel would put enough forces through the shock to get the damping valves working. I'll see how hard and how expensive this all is and let you guys know for future reference. Even I'm interested for my own bucket (but I don't really need it so I wont be silly and buy one until mine stops working someday).

Cheers for the help guys

You're onto it. Low speed compression damping can be (comparitively) very soft on a bucket due to the severe lack of grunt.

ac3_snow
22nd September 2011, 14:21
What are the pro's and con's of using a rs125 or even a rs250 rear shock? surely this would still provide good performance but without the need for all the re-valving and re-spring'ing? or are they not as adjustable as a flash r6 shock? or is it purely a fitment and/or availability issue....

the shock in my bucket is leaking so will need replacement sooner or later, unfortunately most of the stock versions wore out long ago.

F5 Dave
22nd September 2011, 14:29
Availability is a prime factor. Also application. pre 95 were linkless cantilever, post with linkage. They are still a low budget shock, but a racing one for a similar weight bike, so a better starting point.

Buckets4Me
22nd September 2011, 17:52
Availability is a prime factor. Also application. pre 95 were linkless cantilever, post with linkage. They are still a low budget shock, but a racing one for a similar weight bike, so a better starting point.


my pre 95 shock was $1600 new to replace so I dont know where the low budget part came in :shit:

then again it's not standard on rs's either (but a lot of people replaced the standard stuff anyway)

Gigglebutton
22nd September 2011, 18:59
You may be able to get replacement seals for it. I got 2x RS125 shocks from Aus at a good price.

Bert
23rd September 2011, 06:10
gsxr600 shock.........

This is for an RGV250 frame. The shock was real cheap off ebay so I guess extra money could be spent on getting a new spring made.

not sure on your progress here:
but I've been playing around with something similar rgv250 with new shock (common in the UK). the older gsxr shocks pre 2005 fit in the rgv (linkage rates are approximately the same; from what I've read). you will need to mod the dogs to 165mm-170mm as the gxsr shock is a little longer. spend some time read some of these forums (search gsxr shock).
http://www.rgv250.co.uk/forums/index.php?/forum/20-rgv-cosmetic-and-suspension/
plenty of discussions on changing shocks and spring rates by people that have actually done it...