Sorry i know this has been covered many times but where is the best place to get one as i am thinking of changing my current 1 piece.........can the one i have be converted or is it better to replace/exchange it??? will it fit in the tunnel where the existing one goes or is there work needed to fit??? Thanks for any help oh and whats a rough cost.......cheers

A TRT is typically exchange... keeps the cost down!

1 piece no UJ? That's a lot of metal unsupported! Most have a UJ mounted on the side of the drivers footwell. This helps to reduce unsupported weight and reduces torque slap/unbalance.

The new TRT will be of a bigger diameter IIRC 2.5"

Prices vary but between £150-£250 is typical. Dunning & Fairbank IMO are well respected.

Steve

[Edited on 10-2-07 by Hellfire]

Theres a UJ on the gearbox end??? but i don't believe there are any other supports its a straight connection from gearbox to back axle.....sounds daft but the car is not here at the mo and i can't honestly remember seeing any other supports!! do you have a picture?? Thx

Your prop should look like this with a centre bearing,and a sliding UJ at the gearbox end,if yours is a standard MK chassis it will have the centre bearing,this subject has been disscus at length in the BEC section of the forum,check it out

[Edited on 19/05/04 by PAUL FISHER]
Rescued attachment propshaft.jpg

cheers PF i'm sure i don't have the centre bearing but as i said i don't have the car here and as i did'nt build it as stupid as it sounds i don't know whats there. its defo an MK chassis and registered as such but i had the cover off which goes over the gear lever and handbrake (between the seats) and am sure i did'nt see a centre bearing on the prop......is it possible to have one solid shaft (no rude answers!!) or would it be visible from there.........

Yes you would have thought you would have noticed it,the bearing mounts to the drivers side of the transmission tunnel on the MK BEC chassis

Will check it out on Tuesday as the car is in a garage having some work done on the engine and gearbox...............any comments on whether the MK propshaft is any better or worse than the Dunning and Fairbank one as i think i will defo go one or other????? Cheers

The MK propshaft is perfectly fine for any use you are going to throw at it. There are a few points to highlight though:

1. When engaging first gear from neutral there will be a clunk/thud. This how I describe it. The clucnk is still there when changing from 1st to 2nd when not gunning it or driving steadily.

2. No TRT at all will effectively reduce the life of the bike box, especially two up or when driven enthusiastically i.e. trackdays. Most bike box's are fragile for obvious reasons - it's not meant to drive a car. Though I know Paul F AFAIK never had any issues with his. Our's bent 1st to 2nd selector which is common.

With a TRT the clunk is reduced, thereby reducing shock on the gearbox and drivetrain. It will not do any harm for the small initial outlay compared to repairing a box or selector.

IMHO - Steve

Thanks Steve, i had an offroad experience end of last October which left the gearbox making funny noises (it was the road surface at fault not my driving) so having gearbox etc checked over at the mo so was wondering about propshafts etc...i'm normally in it on my own although my son is keen to get me to do some trackdays this year so want to make sure everything is 100% ok...thx for advice

You have a reverse box hence no centre bearing, the one pictured above is for use when you ditch the reverse box (usually because they make funny noises / leak / break )


[Edited on 10/2/07 by ChrisGamlin]

nope..i have'nt got reverse just me and good old manual handling..

You have a centre bearing then, because otherwise you'd know about it due to it breaking and coming through the transmission tunnel!

Seriously though, you'd need a prop of approximately 6" diameter not to self destruct for the length / speed a Locost style BEC needs, and I cannot imagine for one second that MK would have supplied a single piece prop to the original builder, and neither would any reputable prop manufacturer make one if they knew what application it was for.

Sorry to be a duffer but what's a TRT?

Also do MK balance the prop when they've modded it?

TRT = Torque resilient tube

Basically imagine two tubes, one significantly bigger diameter than the other, the smaller tube goes up inside the larger one and you then fill the larger tube with rubber to bond them together. This is how a TRT prop is made, the diff is connected to one tube and the engine connected to the other meaning all the drive forces pass through the rubber coupling which has a cushioning effect and gives you less driveline shunt etc.

[Edited on 12/2/07 by ChrisGamlin]