EDWARD2003

iTrader: (8)

Over the past weekend I had the chance to race my BD7 13' against the local fast guys. I have few chances to race at this carpet facility because it is a 3 hour drive or a 45 minute bullet train ride. So, track time is limited. That said, the carpet track facility is not heated (southern part of Japan don't believe in heating and insulation), so temperatures were hovering around 5~10 degrees Celsius. Tire warmers were required because of the low temperatures and the class I was in - 13.5 boosted. Racing started at 8:30 pm and finished at 12:20 am <---- night racing.

Track layout here http://ameblo.jp/t972113/image-11987...211634518.html

My setup was pretty standard in some areas. (see setup sheet)

It was quite twitchy everywhere, and so I ended up using -20 steering expo and throttle. I think most of my issues were caused by the 13.0 mm rotor. To much torque for a low traction situation. Unfortunately I couldn't change my throttle curve settings on my ESC.

On track handling...

On older Sorex 28's - I started off using Yokomo 450 front and rear, and I noticed the car was suffering from oversteer issues. The front end of the car would dive-in and the rear would start to come around, especially when entering the tight on-off sections, and the middle esses section. So, I went up in oil to Yokomo 550 front and 500 rear and this cured the diving problem and the rear wouldn't come around as much. But, it was still twitchy. As the night wore on, the car continued to oversteer in the tight sections.

New sanded Sorex 28's - I decided to soften the rear by going in one hole on the rear shock tower. This helped a little with the oversteer issues and made the car slightly stable, but now I was suffering slight understeer on the high speed sweeper, also initial and mid corner steering was reduced. However, I did manage to get in a good qualifying time with this setup (qualified 3rd in the A), but still lacking overall stability (twitchy). New tires and dropping temperature could of attributed to this.

So, knowing my car was suffering from understeer from the last qualifier, I decided to move the rear shock out one hole position. Fingers crossed it was going to workout in the A-main with the new tires.

The A-main was interesting, the drivers in the 1,2 position took each other out in the first corner and I ended up taking over the lead. Ha! But, the other drivers behind me were right on my door step. I managed to stay in the lead for about 16 laps. Trust me, it was no easy feat, I was suffering from under steer and over steer all over the track. It was really difficult to drive the car into the corner, and hold the line. Eventually, pressure from other drivers behind me and the overall handling gave way and I spun out... dammit! I did have some assistance from another car, but it couldn't be helped. It was bound to happen. Ended up 4th.

Overall, I was happy with it's first outing and just need to do some more testing. Please help me with some setup suggestions. Please check out my setup sheet and let me know what to change.

tiny tom

Already have a black 14 edition, i brought it second hand to get me back into touring cars. But thinking of getting the 15 edition, is the car worth all the hype?
And the problem I am having is breaking caster blocks, raced yesterday and the car just understeered and just slid into a track marker. But I have broken 3 times in the last 2 race meetings, the car seems weak in this area because I came into contact with 2 over cars and I always come of worst, it has got that bad I have been thinking of changing car to a xray because they seem to be able to take a knock from another car!

atomic garden

iTrader: (1)

@tiny tom

are you using the plastic ones or the carbon ones?

cutting of the axles helps a lot if there are boards you can hit, i had broken 3 before i cut off my axles, and none since,

ofc it could also juts be bad luck, you should measure over a longer period of time

desaix

to EDWARD2003

are you sure about your droop settings? In the setup sheet you posted its Front 5.00 Rear 6.00

I´m pretty sure it should be Front 6.00 and rear 5.00

And I would change rear toe to 3 it could help with oversteer

EDWARD2003

iTrader: (8)

Ah, my mistake. Should be 6 in the front and 5 in the rear.

RedBullFiXX

iTrader: (34)

Yes you should use the plastic ones
Also, the new front DCJ have short axles which are flush with the wheel
BD-010AW

tiny tom

Sorry for the late reply be at work.
I have been using the plastic 6 degree blocks. And on droop 8 on the front and 7 on the rear.
Me hitting the track maker is my fault, but I have been hit twice and done a lot of damage each time. Spoken to my local model shop and they don't know, but one of my caster blocks had a areo bar affect in the caster block. But my confidence in the car is starting to go being 3 bad meetings

RedBullFiXX

iTrader: (34)

Hit stuff Hard and something is going to give

My friends Rays break as much or more than Yokomo

Why the 6* caster ?
Post your setup, maybe we can help get that understeer out
Most Yokomo setups are very close to kit settings window, that's where the sweet spot is

DamianW

iTrader: (5)

The 2015 whilst very similar to the 2014 it drives differently which IMO is better than the 2014, the 2015 produces more initial turn in steering without needing to run a soft front end making the car more stable mid corner and at corner exit.

Re breakages, the bd7 is a strong car.

I ran the bd7 14 last year and broke 2 rear uprights in 12 months racing every week on a tight technical indoor track.

I decided to try the t4 15 this year and whilst it is also a good car it isn't perfect.

There are two big differences between the xray and yokomo, with kit plastics the xray is more resistant to tweak than the BD7 and the xray gear diff is superb (leak free and very consistent) out of the box.

DamianW

iTrader: (5)

With 13.5T boosted even with ultra high grip a 12.3mm rotor is my preference.

EDWARD2003

iTrader: (8)

Thanks , I give the 12.3 mm a try. Switching out to a smaller diameter rotor should smooth things out. I think the 13.0 mm rotor was causing too much longitudinal exit weight at both ends of the car during acceleration and deceleration. Especially with the medium-low traction surface.

tiny tom

Losi 45 weight all round
Front shock 3 droop 8 4.5mm ride hight camber-1, caster block 6 degree which I found easy to drive, if I use 4 it turns in to much.
Rear shock 2 droop 7 5mm ride hight camber -1
The rest of it is kit setup, the steering and caster block are stand plastic, wishbones are graphite and a alloy chassis
Spur gear 114 with 32 pinion gear with 4000 diff oil

RCmcDriver

[QUOTE=EDWARD2003;13836158]Over the past weekend I had the chance to race my BD7 13' against the local fast guys. I have few chances to race at this carpet facility because it is a 3 hour drive or a 45 minute bullet train ride. So, track time is limited....

Might wanna try thinning shock oil the next time. Since it was so cold it could be the skock oil was to harvy for temp.

RCmcDriver

Might wanna try front droop to 6 and rear to 5, and change your camper to -1,5 in rear and ride height to 5 and 5,2.

Lonestar

iTrader: (14)

yup... your 4.5 front droop is the possibly one of the understeering culprits right here.

No matter what - 3 sets of c-hubs in as many race meetings is not supposed to happen... With all due respect, it might be more driver- than car-related.

Paul