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View Full Version : Bmax first run at Stotfold


TheRacePlace
09-11-2008, 05:47 PM
Just got back from stotfold after the BMAX's first run, big bonus was Tom Yardy turning up with his, track was wet and low grip, tom and kev lee taking it in turns to win each round, final standings was Kev by .75 of a second, Tom had the champions pack shocks where as Joe had the moulded ones on, initial impressions are that the moulded shocks worked fine, both cars finished all rounds and final the only issue was Joe loosing a front wheel nut in the third round. those that know the stotfold track will realise a car needs to jump well and handle the bumps, joe started with black springs 40wt front and 32.5 rear (losi oil) tom i believe had 35wt Associated oil but i will leave it to him to confirm, both cars jumped exceptionally well and absorb the bumps, the only issue we had was with steering, lots of initial into the corner but then lost it mid corner pushing wide. after some tips from Yardy senior and a couple of washer it improved but still needs a bit more work, both cars were running 5.5 motors toms gearing 81/21 joe was running 87/18 toms looked perfect in terms of power delivery, joe's needs a bit more playing with to get it spot on.
big thanks to Yardy Jnr and Snr for the help and advice and not a bad start for the car 2nd and 4th.

john

Yardeeee
09-11-2008, 07:38 PM
Yeah I was happy with how my car went today on its first tour of stotfold. I think there is so much to come from the car it's just unfortunate that every time I have ran with it so far it's been in very low grip conditions, but its helped us get a good starting point.

Today we finished up shockwise:

Front - black spring, 35wt oil, champ pack pistons (#2)
Rear - black spring, 25wt oil, champ pack pistons (#1)
(no roll bars, or limiters)

We were geared on 21/81 with a Novak 5.5L

The car responds very well to changes, and is very sensitive to ride height and wheelbase in particular. We finished up on 24mm ride height all round and medium wheelbase, although the car is pretty good on long wheelbase if more steering is needed. On the inboard side, we have added washers to remove any motion forwards or back in the wishbone, and positioning of this washer enables inboard wheelbase adjustment which we have been running on long (washer in front of the wishbone), this give more stability across bumps and enables the car to rotate a little faster in the corners. We also found that running the rear block upside down to give more anti-squat is a good move too.

So far so good, next meeting is on carpet so that will be another school day I guess!

Tom

Yardeeee
09-11-2008, 08:05 PM
P.S. despite Joe having a good day with his new Yoke, his biggest achievement was slipping over whilst marshalling, careering through a pile of wet leaves and pulling a face like a dying fish whilst attempting to get his knees pointing in the right direction again... Legend.

MHeadling
09-11-2008, 09:17 PM
Thanks for the set up info Tom,pleased your getting on with the car, can't wait to run my car next weekend!

Adi
09-11-2008, 09:43 PM
Hello

Nice to hear!

We (swiss drivers) try the car next weekend also on carpet...


For the loost wheel nut, take this ones:

http://www.eseller.ch/images/product_images/popup_images/251_0.jpg

DCM
09-11-2008, 10:49 PM
just drop a little thread lock on the axle after you put the wheel on and before the nut, my Tamiya used to through it's nuts till I did this!

DaveG28
10-11-2008, 05:55 AM
Hi guys,

Was either of Tom/Joe running Lipo, or were you both using nimh? If Lipo how much weight did you add back?

Yardeeee
10-11-2008, 10:22 AM
Both using NiMh.

DaveG28
12-11-2008, 05:32 PM
Tom were you using the champions pack king pins? If so, were you running the steering block low or high?

And for us people not so hot on setups, what does it impact, is it for bump steer??

Yardeeee
12-11-2008, 05:55 PM
Interesting you should ask...

During a test session at another track, when it was very wet and understeer was an issue, just for the sake of it we tride lowering the front hub using the champ king pin. On that day, what appeared to happen was that more steering was gained, in particular at high speed.

I asked Mick Cragg his views on this set up tweak and he said that in their experience, him and Neil had found that lowering the hub just seemed to reduce stability when exiting and entering the corner.

At Stotfold I had the hub lowered all day and the car seemed fine, then for the final we tried raising it again to the standard position and the front end was even better, I found I could be far more precise everywhere and particularly when cornering off camber the car was able to hold a much tighter line.

I can't put into words the theory of what occurs when the hub is lowered, all I can say is that its effectiveness appears to depend on the amound of more technical and complex corners are present in the track... lots of high speed sweepers in low grip condition, lower is perhaps better. More techical tracks, lots of hair pins, off camber sections or bumpy corners, higher seems better.

I have never had a 4wd car where this mod was present so we are just learning at the moment what occurs, but that is what I have found so far, and will more often just use the hub in the standard position.

Tom

DaveG28
12-11-2008, 06:12 PM
Cheers Tom!

Am I right in thinking the adjustment is made just by which way round the kingpin "spacers" are put in, eg with the wide part either inside the hub or outside the hub? Does that mean there's a low, a medium, and a high? I haven't used the parts yet but couldn't really understand the instructions!

Yardeeee
12-11-2008, 06:16 PM
correct