A little suspension setup help? Please?

Hi,
Right this is for my brother's 01 YZ250F, he weighs roughly 175 pounds and the bike is used solely for Motocross at quick Grade C level. The problem he's having is the suspension tends to bottom far too often, even off reasonably small jumps. He broke his wrist recently and is worried if he overshot a jump the bike would come down very hard and injure his wrist again. Plus it's just very annoying to ride when the bike bottoms regularily. So my question is what should he do? It is not really possible to have revalving done here so springs and oil levels are the only real possibilities but we don't know which way to go with them so any suggestions would be great.
Here is the current setup, as it came to us, the bike is second hand from a Grade A rider...

Shock -
Static sag - 15mm
Race sag - 82mm

Fork - (I think I measured this right, if figures sound weird then maybe not :confused: )
Static sag - 35mm
Race sag - 65mm

Stock springs front and rear.

I measured the fork oil level at 80mm but I realised afterwards that there may not have been oil in between the inner and outer tubes so it is probably wrong, could be anything really...

So should he change the springs, and if so what rate springs does he need? Stock fork is .440, stock shock is 4.8. Does .444 and 4.928 sound right(They are from racetech.com).

Thanks for any help :thumb: ,
Philip

OK, thanks guys I'll check the manual and check what the stock fork springs actually are, I just took those from the MX-Tech site. I'll setup the rear sag and sort out the oil level and see what happens.
One thing I assumed the term oil level referred to the distance from the top of the outer fork tube to the top of the oil, have I got this muddled up? Is this actually the air gap, then this air gap should be subtracted from the fork length to get the "Oil level" or what? Anyway the 80mm I gave was from the top of the outer tube to the top of the oil but as I said it's probably wrongs seems as I didn't take the oil between the tubes into account correctly!
What generally causes bent mid valves? Could it be as a result of the A grade rider owning it previously and riding it hard or just one of those things?


Thanks a lot, I'll report back what happens at the next MX - a 100 mile team event, I can't wait for it!

Philip

You were right Marcus, having read the manual we discovered the Euro springs are different to the US ones so here is what the actual springs in the bike are.

Fork Spring - .430 (Unequal pitch) <- Is unequal pitch what is usually termed progressive here or is that something different? The US ones are equal pitch.

Shock Spring - 5.0, 275mm free length, unequal pitch. Again the US springs are equal pitch.

Does this change anything or should we still just try and get the preload and oil level correct frist and try it?


Thanks very much for all the help...

Philip