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Indiana_Jones
7th August 2007, 08:15
Hi guys,

The forks on my bike seem real soft, they seem to bottom out even when i go into a slighty steep gutter.

I have raised the shock at the rear to the highest setting (as I'm pretty tall).

Is this normal?

If not, how would one fix the issue?

It's not stopping me riding, but it is a hassle sometimes.

Cheers

-Indy

Colapop
7th August 2007, 08:17
When was the last time the fork seals and oil were changed? You may have the wrong weight oil in there.
It'd pay to get the springs checked while you're at it.

TDC
7th August 2007, 08:20
What sort of bike is it, how much do you weigh, how tall are you, and any modifications carried out to the bike that you know of?

Colapop
7th August 2007, 08:21
He's about 6 foot tall (standing) and weighs about 45kg! Have a look at the top right of his post and you'll see he rides (or at least steers) a Hooondoggy...

Indiana_Jones
7th August 2007, 08:28
It's a CBR250R (J)

I'm about 6'3" and i'm about 75kg

No mods done to the bike, but the forks arn't the ones the bike came with, as the previous owner fix it after a crash, but they are factory forks I'm pretty sure.

lol 45kg Col

-Indy

Grub
7th August 2007, 08:32
I'm worried that you have started messing with your suspension settings. Pre-load, rebound and all thiose settings are apparently critical to how a bike nhandles and how safe it is. Those settings are different for each rider and take into account weight and height.

I've had the unfortunate experience of going from a bike perfectly set up for me to one that isn't ... it threw me off.

Go and get the forks checked out and then find someone who knows how to re-set all the components

TDC
7th August 2007, 08:44
It's a CBR250R (J)

I'm about 6'3" and i'm about 75kg

No mods done to the bike, but the forks arn't the ones the bike came with, as the previous owner fix it after a crash, but they are factory forks I'm pretty sure.

lol 45kg Col

OK, so the bike has had its forks replaced with something that looks about right? I just had a google for piccys and they are quite generic looking forks and could be off anything in reality.....

First of all you will need to determine if the forks are lacking in damping or springing or possibly both.

Get somebody to help you hold the bike balancing it on the side stand and rear wheel so that the front wheel is off the ground. measure the distance from the top of the dust seal to the triple clamp write this measurement down. Make sure your measurements are accurate!!!

Next have somebody hold the bike upright sitting on its wheels at the point of balance (left right), bounce the suspension a few times measure from the fork seal to the triple clamp, write down this figure. Next press down on the forks and let them return slowly measure again, write down this figure. Next lift the front suspension, let it settle slowly, and measure again, again write down this figure.

Finally with you on the bike in a riding position with your feet on the pegs (somebody balancing the bike) have this measurement taken again, bounce on the bike and take this measurement again to be sure.

Get back to me with the information (pay to PM me so that I remember to check!).

Indiana_Jones
7th August 2007, 12:34
I'm worried that you have started messing with your suspension settings. Pre-load, rebound and all thiose settings are apparently critical to how a bike nhandles and how safe it is. Those settings are different for each rider and take into account weight and height.

I've had the unfortunate experience of going from a bike perfectly set up for me to one that isn't ... it threw me off.

Go and get the forks checked out and then find someone who knows how to re-set all the components

I've only jacked the suspension up so my heat was abit higher, the brike is pretty low as far as sports bikes go. I might take it down a notch or 2.

-Indy

xwhatsit
7th August 2007, 12:45
I'm worried that you have started messing with your suspension settings. Pre-load, rebound and all thiose settings are apparently critical to how a bike nhandles and how safe it is. Those settings are different for each rider and take into account weight and height.

I've had the unfortunate experience of going from a bike perfectly set up for me to one that isn't ... it threw me off.

Go and get the forks checked out and then find someone who knows how to re-set all the components

Regardless of how much he's played around with the external fork settings (and CBR250Rs don't have an excess of settings) he's unlikely to get it so they're bottoming out so easily.

Might've blown fork seals and no/little oil left, sagged out springs, stuff like that. It's an old bike.<hints id="hah_hints"></hints>

Indiana_Jones
7th August 2007, 12:49
I havn't touched the forks myself, only the rear shock.

I donno how old the forks are, as they were brought and installed by the preivous owners due to a crash.

-Indy

Grub
7th August 2007, 12:56
Regardless of how much he's played around with the external fork settings

Nah, it was him saying he'd been messing with the rear that got me worried. Combine that with a dodgy front and it could be a real pig - and maybe dangerous.

Skunk
7th August 2007, 15:28
I'd be following TDC's advice.

DEATH_INC.
10th August 2007, 07:04
I suspect they're just too soft, and come that way. most of the smaller honda's i've seen are like this. 75kg is lots more than the bike will have been designed for too. get some heavier fork springs outta something bigger from a wrecker. that'll sort it.