Yokomo Bmax2 M

[mekios]

What do you mean kicking out?
I had some problems on a same surface, with the end swinging on power exiting corners. I solved it with softer springs and tighter diff (ball diff).

[blue_pinky]

Originally Posted by smokes

Dose Any one have any idea what to change on the kit setup to stop the rear end kicking out on the exits on a dusty astro turf.

using Shumacher Yellow mini spike rear blue insert
Schumacher Yellow narrow cut stagger ribs no insert front

Mid rear Config

Hi...I spent yesterday trying to figure this out too...on very similar track conditions by the sounds of it. I made progress, but not sure I'm 100% there yet.

I built the car using a bit of the Naoto setup from EOS, that setup really isn't meant for our tracks though, and a fair bit of a Maritime setup that got posted on Facebook, but have been gradually been adjusting things according to my own experience of it.

Will try and get my full setup posted at some point, see if it gives you some ideas.

But as a clue.....

Front end
#2 Pistons
AE 35wt oil
AE Yellow BB springs (stiffer than Yokomo X Reds, which are stiffer than kit!)
2 x limiters
Outer hole on tower, middle hole on wishbones
Ride height approx 20mm (not accurately measured!)

Rear End
#1 Pistons
AE 30wt oil
Yokomo blue long (kit) springs
2 x limiters
Inner hole on tower, middle hole on wishbones
Ride height approx 20mm (not accurately measured!)

Weight balance...
605g Front...30g under servo, 20g in front of servo
1039g Rear...75g under lipo

Tyres
New (at start of day) yellow low profile cut staggers
New (at start of day) yellow mini spikes, dboots medium (so chubby!) inserts

I've been using my old centro and it's setup as another reference point for this as it's not dissimilar in a lot of respects (other than the chassis obviously!).

I did some playing with the rear camber link...ended up with inner ball stud on outer holes (so short link), no spacers. Moving it out and down seemed to help catch the rear end on power off the apex's.

It still wasn't totally right by the end of the day, but it's pretty close now I think. Compared to other cars, I'm wondering if track conditions, tyre choice and my throttle control were factors in the loose rear end! At least one of the other cars running ahead of me was on minipins, which seemed to be an advantage.

I qualified 4th and finished 3rd in the A at WORM with that, and was on good pace for me, and running right on pace with the leaders through the day. Comparable to the Centro on a well developed setup when I last ran that, and this was only my first outing with the Bmax2 outdoors, so VERY happy with how it went!!

Will post back when I get the full setup on the sheet.

[smokes]

where did you get the 74g of weight from? I am not sure I need more weight as it turns very well without it.


Current setup

Front

Schumacher Cut staggers on Narrow wheels no foam (new)

Blue kit springs

60WT 800cst associated oil (stopped the front end tramping over the ruts and bumps)

Piston as Yokomo no 2 Taper facing the top of shock

Spacers x2

Middle hole in shock tower
Middle hole in wishbone
Camber link Middle hole one spacer inner hole of the caster block

ride height wishbones level

Camber 1 deg

Toe 2 deg

Rear

Schumacher Yellow Mini pins blue foams (new)

Blue kit springs

400 cst yokomo oil

Piston as Yokomo no 3 Taper facing the bottom of shock

Spacers x2

Middle hole in shock tower
Middle hole in wishbone
Camber link Inner hole one spacer inner hole of the hub

ride height diveshafts level

Supension bush set at 3

2 degrees of anti squat.

2 degrees

No additional weight

Car was great when there was grip
But if you didn't straighten the wheels on and dusty exit before applying throttle it would drift the rear end out.

Normally it should push wide when you apply the throttle on the apex.

I think i may need to trim the outer row of minipins and see if this helps.

And use associated 27.5 in the rear as it feel a little to stiff.

And play around with my speed controller settings.

If I can stop the rear sliding out when I barely touch the throttle I can get a decent time out of the car.

[luniemiester]

I found increasing the rear toe in to 4 degrees made a big difference as well as 2 degrees anti squat instead of 1. Other things to try are shortening the wheelbase both front and rear

[blue_pinky]

Smokes, what kind of track was that setup for?

The 75g weight I put under lipo's was a thin sheet of lead. Not as pretty as brass....but far cheaper

[smokes]

Batley outdoors

[blue_pinky]

Mmm...ok...interesting then!

Well the extra weight I put in was because at Caldicot indoor...running on medium/high grip carpet and a fair bit of polished floor the car lacked grip all round on the slippy bits without it. The extra weight all round helped a lot with that, although I have changed the damping dramatically since then, so may try a lighter car and see what it does now.

The other factor that was based on was both the other mid motor cars I've ever owned (X6 & Centro) have both needed to get up to the 1600-1700g weight mark to get balanced handling, and I've heard the Durango is that kind of weight without adding any extra weight, so figured it was a fair shout that this car could also benefit from it.

So far it has...but more testing as I/we develop the setup will prove or disprove that for sure!

[cryer-evo]

Blue-pinky are you running long rear link ? I have fond it good for rear end grip to the pont where if I get on the gas mid corner it will start to push wide Insted of spin also run 2deg camber on the rear and no spacers in rear our front shocks

[smokes]

Long link make the rear more stable. but slower to rotate.

I think more weight would be benifical as it would give more initial exit grip but can't afford sheet lead or brass weights till the next paycheck to find out.

What springs fit the big bores beside the yokomo and associated springs?

[xfactor]

Springs that fit are losi,kyosho,associated and durango all 12mm springs.

[smokes]

what brand of spring work best in the uk?

[mes]

Found this 50g bulkhead on www.my-yokomo.fr:


Where? When? How much?

[cornishboy176]

I cant see why people are throwing loads of weight in the front of these?

[J'MM'N]

Yes Mes, I came across it this morning, all it says is that its been manufactured by a German racer.

[J'MM'N]

A lot of people add the extra weight up front for extra steering, which I've never found to be a problem. I have added 34g up front though and found the front end to be a lot more stable.

At Kidderminster this weekend took my car to scrutineering only to find it 30g under weight

[cornishboy176]

The only weight i am running is a 79g under lipo weight (and thats only because i am running shorty lipos),Running at Tiverton yesterday our only concern was the front lifting going down the straight (slightly downhill) but we had no problems all day,bags of grip all round,really pleased with how it went, but, I cant seem to work out some set ups i have seen are 50/60 wt oil up front and shed loads of weight up front,correct me if i'm wrong but doesn't that defeat the object

[luniemiester]

I'm running 20g up front purely to help keep the nose down while accelerating and 55g under the lipos to help make the weight limit.

As regards the heavy front shock oils I've gone back to more conventional oils front and rear since I've gone back outside as the tracks are more bumpy and undulating. The heavy oils are more for indoor smooth tracks with high grip as they help slow the cars reactions down more in my opinion

[smokes]

Are the white ball cups stronger than the black
version?

[jonathan may]

I was using 35wt front and 20wt rear with the standard piston it felt very nice load or steering and rear grip on wet grass and astro

[discothesnake]

Originally Posted by smokes

Are the white ball cups stronger than the black
version?

Just the same.