Shock length w. 17" & 18" rear wheel?

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tanto
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Shock length w. 17" & 18" rear wheel?

Post by tanto » Thu Mar 03, 2011 3:18 pm

On the NC30, can the same shock, of the same length, be used for both a 17" & 18" rear wheel?

What modification would be needed to maintain the ride height when the 18" wheel is replaced with a 17" wheel?

I"m thinking of getting a third party rear shock. I don't want to end up having to buy another shock if I fit a 17" wheel in the future. Can the lower link be modified to make up the difference in ride height between the 18" & 17" wheels, without having to change the shock length, or is a new shock unavoidable?

Any advice from our suspension gurus gratefully received!
"A slipping gear could let your M203 grenade launcher fire when you least expect it. That would make you quite unpopular in what's left of your unit." - US Army manual of preventive maintenance.

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Re: Shock length w. 17" & 18" rear wheel?

Post by Hadies » Thu Mar 03, 2011 4:02 pm

Rick Oliver does a jackup kit for the NC30 which includes a rocker and a bottom link. I think you can buy the bottom link seperately though. Its a shorter link which raises the rear a bit.

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Re: Shock length w. 17" & 18" rear wheel?

Post by Hadies » Thu Mar 03, 2011 4:05 pm

Just checked for you:
£85 for the full kit
£60 for the bottom link only

The shorter bottom link gives 35mm rear jack up.

I think I've also seen people drill new holes on the bottom link.

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Re: Shock length w. 17" & 18" rear wheel?

Post by CMSMJ1 » Thu Mar 03, 2011 5:08 pm

RVF lower link... :whistle:
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Re: Shock length w. 17" & 18" rear wheel?

Post by Malc » Thu Mar 03, 2011 5:52 pm

tanto wrote:I"m thinking of getting a third party rear shock.
99 times out of 100 third-party shocks have ride height adjustment (or shock overall length if you prefer) built in.

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Re: Shock length w. 17" & 18" rear wheel?

Post by tanto » Fri Mar 04, 2011 12:51 am

Malc wrote:
tanto wrote:I"m thinking of getting a third party rear shock.
99 times out of 100 third-party shocks have ride height adjustment (or shock overall length if you prefer) built in.
The ride height adjustment is 0 - 10mm, which is probably too little.

Thanks, Hades. I had forgotten the RVF. The "dogbone", or Rick's kit, or drilling the lower link; excellent, plenty of ways to solve the problem. Given where I live, drilling a new hole and welding up the old one would probably be easiest.

Someone take my credit card. Replacement shock websites are coming up on-screen. And, they make them in Thailand... :whistle:
"A slipping gear could let your M203 grenade launcher fire when you least expect it. That would make you quite unpopular in what's left of your unit." - US Army manual of preventive maintenance.

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Re: Shock length w. 17" & 18" rear wheel?

Post by banoffee » Fri Mar 04, 2011 5:53 pm

got one of Rick's lower links on mine. £25 from ebay and was as new :grin:
attention 2 detail - bike valeting and more

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Re: Shock length w. 17" & 18" rear wheel?

Post by thrasher » Fri Mar 04, 2011 5:54 pm

RickOliver wrote:Laying a few misconceptions to rest...

The standard shock length on an NC30/35 is 305mm, not 315mm.

315mm is the length we commonly specify for an aftermarket shock. The 10mm increase when multiplied up by the shock linkage ratio raises rear ride height by around 35mm - this improves cornering clearance and sharpens the steering to just nicely on the quick side of neutral.

If more is good, lots more is not better! A 330mm shock will give a ride height increase of around 75mm and far too much oversteer for comfort - it will make your bike very twitchy, prone to unsettling tankslappers and likely to tuck the front end and dump you in the ditch on tight bends with marginal grip (i.e. almost any `A` road roundabout in the wet...)

Rick

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Re: Shock length w. 17" & 18" rear wheel?

Post by Malc » Fri Mar 04, 2011 6:42 pm

tanto wrote:
Malc wrote:
tanto wrote:I"m thinking of getting a third party rear shock.
99 times out of 100 third-party shocks have ride height adjustment (or shock overall length if you prefer) built in.
The ride height adjustment is 0 - 10mm, which is probably too little.
Yeah, but the extra 10mm isn't 10mm and that's it. There is a multiplying factor involved also, somewhere in the region of 3.5 on the VFR/RVF, so full extra 10mm is about 35mm on the ride height.

EDIT - see Rick has been quoted explaining the same! Great minds, etc... :grin:

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