Upgrading the front end on my PD

Captain Black

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Would a spring upgrade make a difference to complement my new shock factory shock absorber ?

Has anyone upgraded their for springs and to what ? :nenau
 
Did you try to upgrade the originals ?

I put Hyper-Pro progressive springs in. I thought it improved the ride in as much as there was less shock when hitting road "imperfections"
I also used 10w oil.

I think you probably need the Goldvalves to make a real difference, but then again, the Germans call them Gummi-Kuh for a reason :D
 
Stock GS forks are not too bad, with the HPN inserts as good as you will get.

The HPN inserts are NLA but springs to suit them are supposedly available from Hyperpro.
If they are actually the same as the springs as is in the inserts they will be a good match for the #80 /450 lb spring that is Ohlins stock spring for a GS, so it might pay to find out what will be in your new shocks.
With well matched springs you dont need a lot of compression damping, but a bit more rebound seems to work well, and this can be adjusted in your choice of oil in each leg, as one side does the compression and the other the rebound.
But once fitted you wont have anything to post pictures of, which will rule them out for most.

Or you could try the photogenic 50 mm USD's which are fitted to some 90 kg Jap two stroke mx bikes, quite a common fitment but unfortunately no one seems to have a recommendation on either spring or damper rates, and a set of special 12 bolt?top triples seems essential too.
They will require shortening and the 270mm travel reduced a bit to stop your sump hitting the ground on full compression.
They also usually need a wheel, mudguard ,disk and caliper, so the cost adds up but you will be able to start a thread with usually about a 120 posts------------.
 
I'm not sure what oil is in the forks, maybe the first thing to try is a heavier oil ?

Any thoughts on type and viscosity ?
 
Flush them well fit progressive springs (or similar) and don't jump too much on oil viscosity
for example If it's 5w? mix equal of 5 and 10w to give you a 7.5w

Jumping straight to 10w may well make the forks thump as they struggle to compress with the more viscous oil
 
There is a magic formula which involves putting a different grade in one leg because one leg does the compression damping and the other does the rebound. Iput this in mine and it was a slight improvement but that may have just been the effect of new oil. I also think the forks are pretty good anyway - for normal use.
 
Millichamp coctail in the forks helps

Left : 75% 15wt, 25% 20wt

Right : 100% 15wt

The PD models have a 10mm longer plastic tube in the forks for preload
 
if you go down the hyperpro road I recommend getting them from the dutch guys tell them what you want they may be able to supply a non standard unit that will work better for you.
I have non standard springs in the front of my naked rt and they are great.
some of the guys at hyper pro ride airheads and know there stuff
 
if you go down the hyperpro road I recommend getting them from the dutch guys tell them what you want they may be able to supply a non standard unit that will work better for you.
I have non standard springs in the front of my naked rt and they are great.
some of the guys at hyper pro ride airheads and know there stuff

But I don't know what I want :blast
 
It's an option that's better than the standard setup. give it a go before you spend big money. The hyperpro setup doesn't suit everybody.
 
It's an option that's better than the standard setup. give it a go before you spend big money. The hyperpro setup doesn't suit everybody.

I will Rob.
To be honest the bike handles ok solo riding with no load.
I'm only putting the shock factory rear on as I don't trust the OE rear shock with weight on.
I'll play with the front after the TT I think.
 
I'm still running standard front ends on both of my paralevers and have never felt the need to change them. A decent rear shock is all that's been needed on both.
 
Is it worth squirting brake cleaner down the fork tubes to rinse out all the old oil ?

Or do you all just get most of the old oil out through pumping and draining ?
 


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