diff oil advice

xray011 · #1 22-06-2013

Im running xb4 at kiddy tomorrow,and have kit oils in both diffs.
i looked at a few setup sheets and they run between 1000 to 3000.
im expecting a cool day with damp track(please dont rain),would thinner oil help?
also any other advice on setup would be great.....
xb4 is setup as kit settings...

cheers Alan

neallewis · #2 22-06-2013

Thinner oil in the rear certainly helps with a loose back end on slippy tracks.
I used to use 5k front and 2-3k rear, but I've recently gone to 7k front and 3k or 5k rear.

7/5 was ace on the RHR dirt track at the proline challenge, and have been liking how it goes on high traction astro tracks, plus mixed grass and astro of Batley.

I'm running indoors on Yorcc slippy gym floor tonight, so expect i'll need to drop lower again.

I find then running a looser rear oil, the unloaded rear wheel can spin up faster, causing a fishtail when pulling out of a turn and putting the power down onto the straight.

AfroP · #3 22-06-2013

I been running 5k front and 3k rear at seaham on a slippy gym floor/carpet mix.
kept it the same for the regional at dynamix last week and it seemed to be ok.

think i'll switch it up to 7k front and 5k rear for the next regional which is on grass

MeBeMikey · #4 22-06-2013

I was at kiddy a few weeks ago. 10k/5k made car a bit loose on the back end and at times not enough steering on a few sandy corners. If I had the time I would have gone 7k/3kor2k. Loosen your slipper for this track even if its dry. In the wet it's a must. Also might try going up a tooth on the pinion to smooth out bottom end a bit. Astro is quite worn in areas and its s track that I call "slow is fast".

MeBeMikey · #5 22-06-2013

10k/5k is awesome on grass and fast astro like Coventry.

xray011 · #6 24-06-2013

Cheers for the replies guys
I went 5000 front 2000 rear
handled great till i got grip roll.
was running dboots multibytes(i need to get more tyres)
had a great day.
Alan

AfroP · #7 24-06-2013

Quote:

Originally Posted by xray011

Cheers for the replies guys
I went 5000 front 2000 rear
handled great till i got grip roll.
was running dboots multibytes(i need to get more tyres)
had a great day.
Alan

If your running the roll bars front and rear as per kit setup. it may help to remove them to combat the grip rolling.

neallewis · #8 24-06-2013

Quote:

Originally Posted by AfroP

If your running the roll bars front and rear as per kit setup. it may help to remove them to combat the grip rolling.

I never run the rear roll bar now, and am experimenting with light and heavy (than kit) roll bars now. I find they alter the amount of turn in you get on a corner, so tune the under or over steer. These don't really affect grip roll however. Tyres seem to have the most influence.

When I was running at Dynamix high grip astro the other week, I had worn yellow minispikes on the rear, with two outer rows and one inner row of spikes removed. Minispikes on the front were too harsh, so i was running old green schumacher 2 row studs, which gave the right amount of turn in, but no grip roll.
To combat grip roll, I'd say work out of the front or rear is causing the grip roll, then tune tyres accordingly. I little bit more -ve camber can help as can adjusting the roll centres, but tyres are the main tuning aid.