A technical question.
Ive got a marin indian fore trail race xc mtn bk.
At times the front end feel like its going to let go when cornering.
My guess is this is because its a racey set up there is added weight from me on the front end.
My thinking is that with a 120 fork i will ride more upright and therefore put less weight on the front.
Any advice is much appreciated.
Ta

Weight on the front wheel should help cornering grip, unless it feels as though the front wheel is 'tucking under' the bike.
I've been running 110-140mm forks on a 100mm steel frame and it feels OK – certainly more fun on steep descents.

Front end washing out isn't gonna be helped by less weight over it. Have you set the fork up properly, maybe a little more rebound damping to make it slower?

An extra 20mm will slacken the head angle a bit, raise the BB a bit, maybe void the warranty of the frame a bit.

Maybe try the fork or a different front tyre?

I recently upped the travel on my rebas from 100 to 115mm. I think it has made the bike more stable at speed but may have negatively affected the climbing ability. The nose tends to lift on steep stuff and I find I need to move my weight forward on the saddle a bit more. This can all be counteracted by running the fork a bit softer ie more sag. Around this time of year your tyre choice can become critical too. I ride FireXC pros
as a rule but could have done with some trailrakers this afternoon.

thanks for the comments.
I will have a play with the rebound.
I have tried some different tyres…
trailrakers were terrible on the front good on the back
tried my old wtb velociraptor on the front and it felt way better, may have been down to the conditions, not muddy not dusty just sticky!
cheers
oli

You will increase the axle to cown length and therefore slacken the angles of the bike. It could slacken the headangle by 0.5 degrees. teh wheelbase will increase be a few mm also and teh BB will rise by a mm or so.
The result will be a bike more stable at speed, faster at descending but when climbing you will have weight over the back wheel than before so you'll need to lean further forward. You could however drop the stack on your headset if you can, or move to flat bars if you have rises and that will over come the rise in bar height but still keep the slacker angles.

Front end wash out can be a combination of things but usually its poor tyres and bad riding.

he he,
thanks dirtynap,
i didnt have the problem on other bikes but maybe that was the tyres.
would hate to think i'm a bad rider!!