b4 rear tyres not lasting

[darryl]

i'm getting a bit dis heartened about how rapidly the yellow mini pins on the back of my b4 will only last me 1-2 meetings,we race indoors on carpet,and when using a fireblade i could get the tyrs to last around 4-5 meetings,is there any solution which is worth trying to make them tyres last a little bit longer,as looking at the tread all it has done is rounded the pins off but not made them bald????

[Chrislong]

Hi Darryl,
Might help if you back the slipper clutch off a little, so you have about 2yds of slipper slippage rather than wheelspin.

Compare the camber changes on the rear through the wishbone travel on the B4 vs Firecracker, is it much different? Might be that your car is only using 1 part of the tyre rather than the whole width of the tread? Im clutching at straws.

Chris

[Richard Lowe]

It's just the car I'm afraid, it won't tolerate even slightly worn rear tires, with pins at York recently I normally get about 2 races then the rears are shot :o They still have about half the spike left on them but since the car has so little rear end grip you can't get away with it like you could on the B3. I'm disecting my B3 tonight armed with a ruler to see how different the geometry really is...

[burgie]

I'm glad you have found that too - I thought it was just my car that didn't like anything but nearly new tyres. On new tyres the grip is good, but on anything less, it's not there at all, and you can't setup around it. Although, the "top" driver at SRCC, runs on almost bald tyres on his B4, and it still goes like stink!

[Dave G]

thats why i posted in the other section why me,andy and jim dont run at york anymore darryl,its way too harsh on tyres,they dont even last a meeting.thats why it should have much more polished wood(and maybe new carpets that dont destroy the tires..batleys carpet is much more kind to tyres yet still gives plenty of grip)

dave

[Southwell]

Adjust the cars settings to cope with the lack of grip e.g. shorten the wheelbase

[Dave G]

this wont give you grip when the tyres are beyond their working capabilities,fact still remains wear rate is way too high

dave

[darryl]

cheers fella;s,i find the car so tuned in on fresh rubber for one meeting,then the following week with NO adjustments made it handles like (unprintable),so do i spend pounds each week on new tyres or do i trade it in for a blade again (don't shout at me dave) ;D ;D

[Richard Lowe]

Yeah but then you'll need new front tires every race :P ;)

[Chrislong]

What is causing the fast wear rate on the B4? Could it be the internal ratio being lower causing faster acceleration and more wheelspin?

Chris

[Richard Lowe]

That's what I'm trying to track down taking apart the B3 right now, you'd be suppriesed how similar the geometry is, apart from the shock angles, longer chassis and steering arrangement, the suspention geometry is very similar.

Get your ruler out, the B4 wishbones are exactly the same length as the B3, and the shock mounting points are in exactly the same places aswell. The mounting's for the toplink on the front shock tower have exactly the same spacing, the toplink is almost axactly the same length. The only thing thats really changed about the suspention is the rear toplink is less angled in relation to the wishbone, and the front toplink is about 1.5mm higher (box setup) at the inside than the outside. On the B3 the front toplink is 1.5-2mm lower on the inside.

How the heck is the car so different to drive!?

[darryl]

what would happen then if i put the top of the shock in the inside hole i already have the shock in the outer hole on the wishbone,would this generate more grip on the rear ;D

[Richard Lowe]

On the towers, the front outer hole is about the same as the B3's middle, and the rear inner hole is about the same (a little wider) than the B3's middle.

[Southwell]

Maybe it's something to do with the way it handles bumps better might be utilising the tyre better so causing it to wear faster?? ???

Or could be throttle jamming :P ;)

[Richard Lowe]

I think that has quite a bit to do with it, the amount of power we've had available since 3300's came along is silly, I remember when I first got my Cyclone running 12t motors outdoors on a hot day and the speedo would stay stone cold without a heatsink, now I can get it quite warm with a 12t after about 3min even with a thonking great heatsink. ::)

[Southwell]

I haven't run my 3300's yet! Damn snow on sunday! :'(
got my 9x2 on order see how hot my cyclone gets hehehe ;D

[Dave G]

yep the new cells certainly have some effect on tyre wear, as well as the b4 generating obscene amounts of grip the tyre wear is inevitable,yet at batley the tyre wear is far less.only at york do i find that new tyres are a must everymeeting,batley and harrogate isnt as critical or maybe thats just me ?


dave

[Southwell]

At Tiverton i saw the B4 boys going threw 3 sets in the day! My pred lasted all day on one set and still loadsa grip left!
AE should have picked up on this problem and sorted it before release! (unless they already knew)

[Richard Lowe]

The problem is the car's designed for the biggest market, America.
The car's these days are too optimised for dirt tracks, where you tend not to get the front end bite you do on most other surfaces. I don't think the tires are wearing appreciably more on the B4, it's just the car will only tolerate new tires on the back, if they lose a little grip you end up with far too much steering.
I've had the entire indoor season working on this and still hav'nt cracked it ::)

[Southwell]

Think ill stay with my B3. I always go betta with worn tyres! plus my wallet is on fire after buying most my RC kit again this month!
There any other bad points in your view on the B4?

[Richard Lowe]

Nope, outdoors it's awesome, indoors on minispikes it's pretty good, the problems come with the grip yellow minipins generate :o

[BC Rog]

Ok, have a look at what I have said in previous threads .... that is the cause of the problem with tyre wear ... rear end moving around and scrubbing them too much!

With the mods I have done I am getting 2 meetings (on A pace) out of a set of Proline StepPins at Tivverton ....!

The basic problem, as I see it, is that the droop balance front to rear isn't quite on the money (the biggest difference to the B3) and the weight is more forwards than on the B3 also.

If you address the droop balance by putting (lots of) limiters in the front or increasing the rear shock shaft length (my main mod) you are back to having more droop at the rear than the front the car is less likely to pivot around it's front axle thus forcing the rear end to scrub around .... which kills tyres and gives rise to the sudden mid corner release of rear end grip some people suffer.

The upshot of this change in balance is that you have to set the front up slightly softer to get the same steering response which in turn lets the car go over the bumps better. The problem comes when you need lots of front end droop (very rough tracks or slick tracks like Tivvy) and the limiters prevent this .... which is why I devloped the longer rear shock shafts!!

In addition to this running more pack (#3 pistons) in the front will help control the transfer of weight to the outside front wheel from the inside rear. This too prevents the unloading of the rear end and thus the pivoting / scrubbing effects.

It's worth a try and all how have tried it have given positive feed back.

Rog

[Declan]

I wouldent really know but i think mini pins arnt the best tyres to go for every one where i go uses rally blocs schumachers.from Dec ;D ;D ;D ;D ;D ;D ;D ;D

[darryl]

declan mate,were talking buggies here not tourers ;D

[super__dan]

Daryl, My rears on Sat had seen better days but I still got understeer, reason being the fronts were twice as old as the rears. What I think is the way to go is run 2 sets of rears for every 1 set of fronts.

Now the regionals have finished and its just club racing I think I might buy tyres sets in 3's, 1 front and 2 rears. Then when I stick the new ones one regularly swap the rears over to maintain the balance of wear to the fronts.

In an ideal world alternate the rears sets every single run, though maybe not quite this much, I'm sure you see what I mean.

Dan

[darryl]

hi dan
im going to run a fireblade on satyrday,used to use one of these before,using relativly warn tyres just to make a comparison,just cant seem to justify spending out money each week just for club racing,and me being a right scrooge as bruce and the others will tell you :P

[super__dan]

Nooooooooooooooooooooooooooo, don't do it! Glad I won't be there to see this travisty ;)

Dan

[darryl]

your just jealous that you wont be there to have a go, but you see my point,as it reflects in this thread ,i'm not the only one who has problems with the rear end slipping about as though it's on ice,who knows i may even stick with the blade :o

[Southwell]

Sell em both and get a xxx ;)

[super__dan]

Dear god, this goes from bad to worse, has the world gone mad? ???

Dan

[Chrislong]

Dan, let him sleep, tomorrow he may realise what he has said and burn the Blade in disgust.
;D
Chris

[Richy]

does it go through tires fast on carpet or on grass to :(.

[burgie]

if you are going through tires so fasy, why not run a harder compound, and adjust your setup/driving style to suit?

You can't expect to run soft compound tires and expect them to last....thats just muppetry that is.

[darryl]

muppetry chris,i think you'll find and quote me if im wrong ,but other than schumacher yellow compound,there isn't another tyre that works on carpet,a harder compound will last longer as you will get no grip at all

[burgie]

erm, I actually run blues on the carpet I race on and I have set up around the problem and have grip.....it's entirely possible.....

[super__dan]

You must run grippy carpet then, cos blues would be toss at York!

Also copying Steve Wright's catchphrases is very uncool, he is a gimp and should not be followed under any circumstances.

Dan

[Richard Lowe]

Hahaha ;D

Don't worry Rich, it's just minipins it eats, outdoors is no problem. (/wipes brow)

Blue's can be used indoors, they're just useless compared to yellows, 0.5sec per lap easy!

[Richy]

Thanks thats a big relief because I had a Fireblade and I just bought a B4 thinking they looked very good on the track but I don't run it indoors I use my Boring Car ;D.

[Chrislong]

Its got to be yellows, as blues or greens would be cack on the polished gym floor surfaces which York, Batley, Harrogate, all use so much in the NE.

Chris

[burgie]

Also copying Steve Wright's catchphrases is very uncool, he is a gimp and should not be followed under any circumstances.

Dan


I never claimed to be cool! But you obviously listen too..... ;D

[super__dan]

Also copying Steve Wright's catchphrases is very uncool, he is a gimp and should not be followed under any circumstances.

Dan


I never claimed to be cool! But you obviously listen too..... ;D


Sprung :-[

In my old job I used to listen to the radio for 11 hours a day, 3 hours of which were Steve Wright annoying me by being the slimiest git on the radio..

Dan