Fork preload?

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JamesinEdinburgh
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Fork preload?

Post by JamesinEdinburgh »

Dave Lambeth advised me to pre-load my 3AJ front forks rather than buy new Wilbers et al springs.

I fitted a couple of hard plastic 10mm preload discs for my T7 from Rally-Raid and they worked really well.

Has anyone fitted 10mm preload discs to an old Tenere?

Or can recommend a source?

:thanks:
donnybach
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Re: Fork preload?

Post by donnybach »

What condition were the original springs in? Still within spec and equal?
I need more force front and back so I’m interested.
And does that eliminate the air pressure or do you not pump up 3AJ forks anyway?
sandlover
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Re: Fork preload?

Post by sandlover »

put 20 w oil in mine and they are much better on and off road.
Doubleyoupee
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Re: Fork preload?

Post by Doubleyoupee »

JamesinEdinburgh wrote: Tue Jan 31, 2023 11:28 pm Dave Lambeth advised me to pre-load my 3AJ front forks rather than buy new Wilbers et al springs.

I fitted a couple of hard plastic 10mm preload discs for my T7 from Rally-Raid and they worked really well.

Has anyone fitted 10mm preload discs to an old Tenere?

Or can recommend a source?

:thanks:
Hi,
Wondering if you had any more information on the above?
Why did he recommend pre-loading the stock 3AJ forks? How much did you preload it for?
As far as I know, peloading a spring doesn't increase its spring rate so you're still stuck with the very low stock spring rate.
Thanks
JamesinEdinburgh
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Re: Fork preload?

Post by JamesinEdinburgh »

I ended up putting YSS PROGRESSIVE Fork Springs 35x632mm springs in

You can see a picture here viewtopic.php?p=37646#p37646

There is one more pair available here https://www.ebay.co.uk/itm/303505374374

Sag was a lot better. Probably should have put thicker oil in.
Doubleyoupee
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Re: Fork preload?

Post by Doubleyoupee »

JamesinEdinburgh wrote: Thu Apr 18, 2024 1:12 pm I ended up putting YSS PROGRESSIVE Fork Springs 35x632mm springs in

You can see a picture here viewtopic.php?p=37646#p37646

There is one more pair available here https://www.ebay.co.uk/itm/303505374374

Sag was a lot better. Probably should have put thicker oil in.
Thanks,
They look to be very similar to the Wilbers one, also measuring 632mm. Although the Wilbers are 4-6.5mm N/Nm while these appear to be 4-7.0.
How did you like them? Not too stiff?

I am still curious why David would advise against new springs (or at least recommend preloading the original). The spring rate of the stock one is supposed to be 2-4.5mm N/Nm which is very soft.
scottieh
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Re: Fork preload?

Post by scottieh »

Doubleyoupee wrote: Fri Apr 19, 2024 2:52 pm
I am still curious why David would advise against new springs (or at least recommend preloading the original). The spring rate of the stock one is supposed to be 2-4.5mm N/Nm which is very soft.
If you change the front fork spring rate i highly recommend changing the rear spring to match or your riding geometry will be super funky. On my 1VJ I swapped my front and left my back end original and had all kinds of problems with speed wobbles on tarmac and loss of front end control in the dirt. I’m not sure of messieurs Lambeth’s reasons but in my experience i highly recommend doing both at the same time.
Doubleyoupee
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Re: Fork preload?

Post by Doubleyoupee »

scottieh wrote: Sat Apr 20, 2024 1:45 am
Doubleyoupee wrote: Fri Apr 19, 2024 2:52 pm
I am still curious why David would advise against new springs (or at least recommend preloading the original). The spring rate of the stock one is supposed to be 2-4.5mm N/Nm which is very soft.
If you change the front fork spring rate i highly recommend changing the rear spring to match or your riding geometry will be super funky. On my 1VJ I swapped my front and left my back end original and had all kinds of problems with speed wobbles on tarmac and loss of front end control in the dirt. I’m not sure of messieurs Lambeth’s reasons but in my experience i highly recommend doing both at the same time.
Yeah, that makes sense.
For me it's the other way around. I have a stiffer spring on the back (unknown rate but rear is higher now) with stock forks at the front.
I now switched to Wilbers progressive springs in the front.
Hopefully they match OK enough
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