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r2rocket
09-06-2011, 07:09 PM
Just curious how much preload on the left rear shock when trying to adjust the byte is too much preload?

JTSjet
09-06-2011, 08:52 PM
how soft of a spring are you running? how much bite are you trying to get?

C10
09-06-2011, 11:05 PM
with a 225 14 inch spring, with 130 pounds of bite I am about 2 to 3 turns from seating the top of the spring at full drop. When the track slicks off I put those turns in untill it contacts the spring and roll about 2 turns in the lf (usually half what I put in the lrr spring) to put some tilt in the car. This is on a Rocket black car

Kwaz-13
09-06-2011, 11:57 PM
Fought this problem on an older GRT, and there are some posts around here somewhere. You may have already looked into this, but here it is.

I found two things that had a serious affect bottoming LR adjuster:
-RR ride height too high
-4 bar chassis mounts not on a radius

I'm not familiar with Rocket chassis, so don't know your ride height or how you set it. But, setting the RR too high meant that we were needing every possible turn in the LR just to get bite. Realizing this was worth about 100# bite. (1-1/4" difference in height)

The second problem which I haven't attended to yet was that the LR 4-bar mounts aren't set up with enough radius to move bars without changing their length. For instance, lowering the bottom bar (without changing its length) indexes the birdcage. After moving it down, we have to use a jack just to put the bar in the hole. In other words, the LR is preloaded A LOT more than what you are describing. I also believe our birdcages may be an issue, as they are not factory.

Good luck!

C10
09-07-2011, 01:36 AM
yes you are correct, but in the Rocket book this method is the recommended way to set the bite after all the ride heights are correct. If you go way off on heights you will need to 4 corner to maintain them, but you should be about 2 to 3 turns to seating the adjuster at around 130 if everything is rocket pieces

Kwaz-13
09-07-2011, 07:07 PM
Sorry C10! It was late, and I mistakenly thought that your post was r2rocket's follow-up! Agree with everything you posted.

C10
09-07-2011, 10:48 PM
Not a problem Sir! We had the same objective, to help a fellow racer! Have a good one!

r2rocket
09-10-2011, 02:50 PM
We dont run Rockets anymore. We run BWRC. I really havent heard an answer to the question yet. Is it unusual to preload a lr spring 5, 10, 15 rounds to achieve the #byte desired? Thanks again for any feedback.

jedclampit
09-10-2011, 03:35 PM
Kind of a loaded question, as it varies with how much drop, coilover mounting points, shock configuration( space between mounts), left side weight etc.
With that if your @ 13.25 drop a couple of rounds of preload w/a 225 is in range normally.
When you get really soft on the spring(130-175) it can be preloaded so much you need a fixture to get preload where it needs to be.
Preloading shouldn't pose any problems.
Hope that answers what your after!

r2rocket
09-12-2011, 11:03 AM
Yes, this helps. Thanks!

Kevin20ump
09-12-2011, 11:58 AM
Yes, this helps. Thanks!

What LR spring are you scaling with? We have a 2011 BWRC.

Kevin20ump
09-12-2011, 11:59 AM
Send me a reply to my PM