201 setup help

[Quantra]

Hi everyone, my first post here and I'm looking for some help please.

I have a TRF201 as the latest cure to my Tamiya addiction. I am still fairly new to RC as a whole and pretty much brand new to 2WD buggy racing.

I race at my local track (HNMC) which is astro turf. I am using pretty much stock setup given in the manual with yellow mini spikes on the rear and stagger ribs on the front. The problem I have appears to be far too much front grip.

In the dry the car grip rolls on every single corner unless I run some crazy positive camber. I believe this makes the car feel very on edge too.

In the wet as soon as I touch the throttle the car spins out, I managed to combat this last race by using brand new rear tyres.

I was thinking about trying some normal rib tyres (if that's the correct term) to reduce the grip at the front. Is this a reasonable idea or a big no no for astro? If so any suggestions on what ones to try?

Also does anyone have any suggestions on what I can do to make this car settle down and drive as stable as my other Tamiyas?

Any advice is really appreciated as there is no one else that runs a Tamiya at the club I go to and I just love my Tamiyas too much to buy anything else. Right now, though, I feel a bit in the dark being a newbie alone in the mine field that is setup.

[cjm_2008]

couple of things worth checking:

1. slipper clutch - does it actually slip when you apply the throttle?
2. dampers - do they move smoothly?
3. ride height - with all the radio gear including battery, how high does the rear end sit? the driveshafts should be level (i.e. a straight line across the horizontal axis).

definately worth expermenting with tyres too - they're usually the first port of call, but it sounds like there's something in your setup that is compromising the way the car works the rear tyres - too much power, to agressive throttle curve, or possibly a trigger happy left thumb!

[DCM]

1.3mm pistons and 35wt oil up front, can't remember the springs. Kit camber link location and shock, 1.5-2' camber.

1.4mm pistons, 30wt oil rear, silver b4 springs (or Tamiya equivalent). Kit camber locations and 1-2' camber. If grip rolling on corner entry, remove out row of spikes on the rear.

[Lee Martin]

Which staggers are you using on the front?

[Quantra]

Thanks for the responses so far.

Originally Posted by cjm_2008

couple of things worth checking:

1. slipper clutch - does it actually slip when you apply the throttle?
2. dampers - do they move smoothly?
3. ride height - with all the radio gear including battery, how high does the rear end sit? the driveshafts should be level (i.e. a straight line across the horizontal axis).

definately worth expermenting with tyres too - they're usually the first port of call, but it sounds like there's something in your setup that is compromising the way the car works the rear tyres - too much power, to agressive throttle curve, or possibly a trigger happy left thumb!

1. Yes I have been experimenting with this, even had it so loose at one point it glazed the pads. It's now set so it slips for about 8-10 feet off the line.
2. Yes they are buttery smooth. I built them as per the instructions but used the bleed screw and packed the o-rings with green slime.
3. I'm running roughly 24mm at the front and 25mm at the rear.

Power might be the issue as in the wet I literally have to touch the throttle for it to spin and I have stripped teeth off the stock idler(now using reinforced one). On the straight it can do 35-40mph. Normally I like a linear throttle curve but I will experiment with the exponentials when I can. Would a smaller pinion help?

Originally Posted by DCM

1.3mm pistons and 35wt oil up front, can't remember the springs. Kit camber link location and shock, 1.5-2' camber.

1.4mm pistons, 30wt oil rear, silver b4 springs (or Tamiya equivalent). Kit camber locations and 1-2' camber. If grip rolling on corner entry, remove out row of spikes on the rear.

If you can remember what springs on the front I'd likely try this out. What is this suggestion based on?

Originally Posted by Lee Martin

Which staggers are you using on the front?

They are Schumacher stagger ribs with half a rear insert cut and put in. The Schumacher rep fitted them for me.


I thought it might be useful if I posted my full set up and some pics so here you go:

TRF201
Fusion Exceed 6.5T (7400kv)
Fusion Exceed Pro 80A (Lowest start power, soft power curve, lowest acceleration, 35% punch, no timing)
NLB 5000mAh 35C
Stock Hyper 7 servo
Ansmann W6 radio gear

All shock positions, camber link positions, toe in etc as per the manual
Kit springs and oil
Narrow wing for dry, wide for wet
Camber: Front +4, Rear -2.5
Stock spur, 22T pinion
Ceramic diff balls
Aluminium rear suspension mounts (3 degrees)
Lightweight motor plate







Sorry some of the pics are a bit shoddy, if better ones would help let me know and I'll try harder

[Lee Martin]

well the schumacher rep has fitted them wrong for a start.

Normally you should cut the wheel down (width) to the next rib. and not run an insert.

Shorten the front link on the hub.
Give yourself negative camber. this positive camber will make things worse.
more the front shocks out on the arm.
Load your car up with Rudebits Brass.....
80g under lipo
heavy under servo.

and you will be fine!

Lee

[cjm_2008]

Originally Posted by Lee Martin

well the schumacher rep has fitted them wrong for a start.

Normally you should cut the wheel down (width) to the next rib. and not run an insert.

Shorten the front link on the hub.
Give yourself negative camber. this positive camber will make things worse.
more the front shocks out on the arm.
Load your car up with Rudebits Brass.....
80g under lipo
heavy under servo.

and you will be fine!

Lee

listen to this guy - he knows what he's on about

[Quantra]

Originally Posted by Lee Martin

well the schumacher rep has fitted them wrong for a start.

Normally you should cut the wheel down (width) to the next rib. and not run an insert.

Shorten the front link on the hub.
Give yourself negative camber. this positive camber will make things worse.
more the front shocks out on the arm.
Load your car up with Rudebits Brass.....
80g under lipo
heavy under servo.

and you will be fine!

Lee

Cheers Lee I'll have a go at removing those tyres and refitting them properly. I'm sure either brute force or acetone will get them off

By shorten the front link on the hub do you mean just turn the turnbuckle to make it shorter or move the ball studs closer together (and adjust the turnbuckle)? Sorry for my ignorance! What effect does moving the inner ball studs to the outside position have?

I've aquired some lead flashing to play around with weight as I can't afford rudebits this month so I'll try and match the weights/positions as best I can until next month.

Originally Posted by cjm_2008

listen to this guy - he knows what he's on about

So I've heard Seriously though I'm well chuffed he takes the time to help beginners like me. Tamiya are lucky to have him and I'm hoping by indirectly sucking up to him he'll come back and answer more of my novice questions

[Lee Martin]

haha! of course i will answer!!!! ill even be at Herts this weekend on the sunday for the 8th national if you wanan pop over and say hi.

Right - Move the ball stud (on the caster block) to the inside position. this will make the car steer harder into a corner.. but less coming out, reducing mid corner grip roll.

leave the inside one alone

load up that weight!!! get as much as you can in there!
then use a ride height gauge (LMR one of course) and set it at about 21mm all round. this should be low enough to reduce grip roll and still allow the car to have some body roll into a corner.

Lee

[Lee Martin]

also reading your set up...maybe look into buying some option springs. Blue fronts and yellow rears would be ideal.

Lee

[Quantra]

Nice one, I have a race tomorrow and I've managed to get 50g under the lipo, 20g around the servo, 10g behind the nose cone and 5g in the nose cone. I'll give that a go and see how I get on.

The ball stud on the caster block is already on the inside position which is why I asked about moving the one at the base of the shock tower (only way I could see to shorten the link).

I take it those are the Tamiya option springs 53975 and 54221.

I should be able to pop over on Sunday to say hi but if you want to come a day early I'm sure no one will notice if you drive a couple of rounds for me I'll even let you kip on my sofa

[Quantra]

I refitted the tyres, dialled in -1 degree of camber on the front, moved the front shocks out on the arm and loaded up on weight as before. I also dropped the pinion by 1 tooth.

The car now looks a bit closer to the rest on the track, it was easier to drive and the slower speed gave me more confidence. I think I now have a starting point where I can make further tweaks, thank you.

Sorry I couldn't pop over to say hi yesterday, had a family emergency and sadly one of the elder generation passed away.

I've ordered some springs and added some more weight to the car too, so I will look forward to trying that out next time.