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Welding Bias Bar for IVA
big-vee-twin - 14/12/09 at 10:41 PM

Has anyone one gone through IVA with a balance bar yet and did you weld up the threads or do something else?

Seems a bit drastic to me but that is what it says in the Manual - any thoughts?


loggyboy - 14/12/09 at 11:25 PM

I plan on using a ral des pedal box, that has a £16 replaceable balance bar, so il weld that, then swap once its thru IVA.


Findlay234 - 14/12/09 at 11:27 PM

I have, it does say that you have to weld it up and I didnt.

You have an age old catch 22. do you go to the IVA with a welded up bias bar and have the possibility of failing on bad brake balance or just generally bad set up. Or do you go without welding it up, pass the brake test and then fail on not having welded it up. what to do what to do..... i went without welding and it passed just fine...


blakep82 - 14/12/09 at 11:51 PM

wonder if my old gasless mig would work on one of those power inverter things plugged into the car, just enough to weld the balance bar while actually at the test?


loggyboy - 15/12/09 at 12:41 AM

Just take the car to an MOT centre prior to IVA, dont get them to run it thru the books, its a good way to check general items anyway.


britishtrident - 15/12/09 at 08:09 AM

MOT roller brake test is useless for setting up front to rear brake bias.

Only method that really works is road test on smooth clean dry surface ---- can be done at very low speed.


Findlay234 - 15/12/09 at 09:04 AM

I did the road test as britishtrident has mentioned and checked the bias that way. (didnt need adjustment and then passed IVA)

Think if youve used the right mcyls for your brakes front and rear then you shouldnt really need any adjustment on the bias bar, just have is set central.


big-vee-twin - 15/12/09 at 09:29 AM

I've got 0.7 for the rear and 0.625 for the front
do you think that would be ok without to much adjustment?

I thought about using liquid metal to make the bar un-usable after adjustment at the IVA then changing it later


prawnabie - 15/12/09 at 10:06 AM

Don't forget that for IVA you need a minimum of X% on each axle in case on failure!


Dangle_kt - 15/12/09 at 10:14 AM

I welded mine ( sva but I lost my roll pin kit the night before the test!)

two small spot welds, worked fine with no problem.


MikeR - 15/12/09 at 10:42 AM

IVA says the whole bar must be welded.

Wonder if you could use some sort of braze / solder / liquid metal.

If you get it wrong, heat it up / retap it, adjust and reset. Sort of sticks to the rules and sort of gets round them in case you're wrong.


Neville Jones - 15/12/09 at 01:00 PM

Not that I would do this, but a nut with a small piece if threaded bar welded on the end,so a few threads were still visible, and threaded onto your balance bar, would look a lot like a nut welded to the balance bar shaft???

Just fill any gaps with washers, and tighten it up.


NS Dev - 15/12/09 at 01:58 PM

Think I've wobbled on about this one before.......

I can't believe that the writers of the manual are suggesting welding a piece of threaded bar, which is safety critical, and subject to severe cyclic bending stresses!!!

I am no aircraft engineer, but this is the ONE piece of the car you would NEVER want to weld!! I guess as long as the weld is outside the clevises it doesn't really matter, but its only a matter of time till somebody welds it somewhere between the clevises ans the bar snaps a couple of years down the line.

The bias bar is thin enough already for the bending loads on it, whatever you do don't weld it between the clevises!!!


Lightning - 15/12/09 at 02:45 PM

I had contemplated welding a small section of stud that is half way through a nut. With this scewed on tight to the end of the balance bar. Would look like welded but could be unscrewed after. But that would be wrong and I wouldnt do things like that.


rickys2000 - 15/12/09 at 06:25 PM

Mine was spot welded for IVA. Put a locknut on against main unit and welded bar after the locknut and passed successfully. (does that make sense, I just read and am not sure. it worked though) Thereafter it was cut off and replaced with fully adjustable system!