Wheel offset Vs Bearing load

**oldcorollas** · 30-11-2007, 02:31 AM

just calculate it

lever rule, distance between bearing and rim centre, and between bearing and diff.. due to leverage there will be small increase in load on bearing..

however, bearings are ridiculuosly strong when loaded radially

usually when engineers have a shit abotu bearings, it is because of increased weight, or more usually, because you have increased the side loading capability of the car...

**allencr** · 30-11-2007, 02:59 AM

The leveraged increase in load isn't much by appearance, with having the same static& straight line weight and I'm clueless about calculating the greater dynamic weight it gets with side-loads & going over bumps in turns. I think most stories about bearing failures are just about something that was ready to go anyway - anecdotal. But I think that along with that increase, wouldn't it also be in a slightly different position on the race and wouldn't that speed up its wear or even destroy it, being a 'well broken in' bearing , even ones that are new, having been replaced last weekend with the help of some friends & liquid gold?

**JustenGT8** · 30-11-2007, 08:21 AM

With a quality manufacturer like H&R making up to 65mm bolt on spacers to increase wheel track (on IRS suspension too) i can't see your 25mm causing any issues at all.

I have been running H&R 25mm spacers on the GT8 since it's been running and also on my other GT4 prior to that, so a total of some 6-7 years now....never had a bearing prob and both cars saw the track as well as many hard street driven km's.

**Hiro** · 30-11-2007, 08:54 AM

Originally Posted by oldcorollas

just calculate it

lever rule, distance between bearing and rim centre, and between bearing and diff.. due to leverage there will be small increase in load on bearing..

however, bearings are ridiculuosly strong when loaded radially

usually when engineers have a shit abotu bearings, it is because of increased weight, or more usually, because you have increased the side loading capability of the car...

Yeah, thrust loadings in the SAE car were the worst loads, and were significant because we were using deep-groove ball bearings instead of the standard practice of matched tapered roller bearings in cars

**The Real Roadrunner** · 30-11-2007, 10:44 AM

as has been stated there would only be a mild increase in bearing load on a live or IRS rear, the only thing i would be concerned about is if the axle flanges are big enough to take the extra load that would be applied to them.

but having said that if your using a borgwarner out of something that ways around 1400+ kilos and survives in a taxi for 300,000+kms commonly used for takin 4 120kgs+ drunk blokes home with 3 of them hurling out the window then i think you will be just fine

cheers
linden

**30psi 4agte** · 01-12-2007, 06:07 PM

Good point /\/\/\/\/\

BTW........ I fucked up and had a blonde moment

( thats what you get when you work for over 30hr straight)

I worked out the rear spacers needed using my front rims with 205's on em not the rears with 225's on em

I only need 12mm spacers now .... Which i have no concerns with using ..

Im only human....

**The Real Roadrunner** · 01-12-2007, 10:06 PM

12mm spacers could get sketchy, just depends if there bolton or not and also how deep the studs sit into the back of them. what material are you going to make them out of ?

cheers
linden

ps i know what 30hrs straight does to you and it aint nuthin good.

**30psi 4agte** · 02-12-2007, 06:43 PM

Im just using a "slip on spacer" ........But im machining it to suit. So it will locate on the axle and also have a locator on the outside of the spacer ( snout ) for the rim. I will also drill a retaining bolt to hold the spacer to the axle.

making it out of alloy.

will post a pic as my decription is a bit vague

Linden : You'd know me fairly well by now.....So rest easy as its up to scratch with the rest of the car !

**The Real Roadrunner** · 02-12-2007, 11:32 PM

yeh ive done the same thing for a pug with brembos on it, but i uses an alloy spacer and put a steel insert to locate the rim and hub. ans it was bolted through the disc and hub.

cheers
linden

**auzzi_17** · 06-12-2007, 03:53 PM

I just put a set like these on my 74 celica. Because its self locating on the inside and produces a locator for the mag, it shouldnt have much affect on bearing load. Ive got 25mm on the front and 30mm on the rear.

http://tbn0.google.com/images?q=tbn:...S/PICT0001.jpg

**clubagreenie** · 06-12-2007, 05:20 PM

Using Stuarts/Stewarts? load calc theories, compare to bearing load rating info available from the bearing co you buy from. (you don't buy genuine do you). Or a more tech question for the bearing merchant, does the taper angle alter the capacity (for cup/cone type) or smaller and more needle rollers with smaller pressure points, more load distribution; or larger, fewer for sealed roller bearings.