Centerlock tightening

[Simon T]

Impact wrench, either a 24v battery one or preferably an air driven one with a good head of pressure behind it. If that fails heat if that fails drill ( I have had to do the latter). The surfaces of both the nut and the wheel need to be free of burrs. A thin smear of WD40 on the mating face and the threads works wonders at stopping this happening

[splitpin]

Any joy?

If not, further thoughts >

1) Have you tried a bit of carefully applied heat?

2) Decent sized person (or a couple of really big bags of spuds etc) sat on subject wheel may well help resist turning even when brakes applied.

3) A 'take it by surprise and whack a conventional impact driver with a beefy old lump hammer' is often more productive than a long lever torque bar or a rattle gun. At the start, remember to whack it a couple times in the tighten direction before trying to undo it. I was going to say clockwise/anti-clockwise, but of course that depends which side!

Obviously the above can be done in various combinations.

HTH

[sweetmate]

As mentioned before good strong breaker bar with 2 meter long Scafold tube slid over should do the trick. Wd 40 the nut and wheel as well before that should get them off

[jpivey]

When I had a prosport on centre locks had the same issue I used to wedge a piece of wood into the wheel that would jam against the upright and with enough force bingo....

[mnrvortxf20c]

got them off.just finished now! took 3 of us in the end.one on the foot brake, 1 on the wheel stopping it turning,and me on the giant torque wrench! there was small rust spots on the face of the centre locking hub adaptors so im assuming that was the issue! anyway at least i can use the car as planned on friday! cheers guys

[Coldaswell]

What are the centre lock hub adapters made of?

I believe (and may be wrong) that if you have steel and ally alloy in contact without something like copperslip between them and you get any sort of oxidation, the two parts will seize.

[Coldaswell]

Googled it. Where two different metals have an electrolyte is introduced between them (ie water) a "galvanic reaction" will take place. If the metals are in contact such as the mating surfaces of the wheel nut or the nut and thread, this may cause them to seize.

Use of a separator will prevent this, eg greases / copperslip, which is what I use.

There must be someone with more knowledge or experience of this here.

[LCM]

radicaltechnical said:

please see below for torque settings on a Radical.

TORQUE GUIDE FOR RADICAL CARS

(MEASURED IN FT/LBS)
L = LOCTITE
L/T = LOCKING TABS
L/W = LOCK WIRE
R = ROLL PIN

DRIVE SYSTEMS
POWERTEC SR3 DRIVE UNIT RATIO NUTS (L) 80
POWERTEC SR8 QTEC END NUT/BOLT (L) 200
HEWLAND GEARBOX PINION NUT BEARING (L L/T) 150
CROWNWHEEL BOLTS (L L/W) 70
PINION END NUT 75
SR4 DRIVESHAFT NUTS (R) 180
SR4 REAR SPROCKET (L L/T) 50
DRIVE UNIT CROWNWHEEL BOLTS (L/T) 60

WHEEL BEARING/HUB NUTS
FRONT SR4/PRO6 180
REAR ALL MODELS (L/T) 260

WHEEL NUTS
CENTRE LOCK NUTS 240
4 STUD 70

ENGINE OUTPUTS
SUZUKI HAYABUSA WITH SPROCKET (L) 115
SUZUKI HAYABUSA WITH DRIVE COUPLING (L) 115
KAWASAKI WITH SPROCKET (L L/W) 90

UPRIGHT BOLTS
FRONT/REAR UPPER BOLTS (L/LW) 40
FRONT LOWER BOLT (L/LW) 100

BRAKES
FLOATING DISC TO BELLS (L/W) 8
BRAKE DISC TO HUB BOLTS 80

HAYABUSA REAR ENGINE CRADLE 45

Now, I don't want seem a boring old pedant, but isn't it ftlbs (or lbsft for young folk, or indeed Nm for those both young and scientifically trained) rather than ft/lbs? Multipying two numbers together gives a slightly different outcome from dividing one by t'other

[LCM]

Coldaswell said:

Googled it. Where two different metals have an electrolyte is introduced between them (ie water) a "galvanic reaction" will take place. If the metals are in contact such as the mating surfaces of the wheel nut or the nut and thread, this may cause them to seize.

Use of a separator will prevent this, eg greases / copperslip, which is what I use.

There must be someone with more knowledge or experience of this here.

You're right!

Even in these dumbed down times, this is basic GCSE chemistry.

Frankly, if you torque centre lock nuts up, use the car and then leave them torqued up for a week, you deserve all you get.

The reason I gave DoctorDave a 5' torque wrench with Betty was not so much for tightening the centre lock nuts to (the old standard) 180-200 ftlbs but undoing them after a day’s hard driving when I've known it take 400 - 500 ftlbs to crack them off.

There are two approaches to caring for centre locks

• the surgically clean and dry approach
• the sort of clean and Copperslip approach.

There are happy users of both appearing on here. I've tried both and have settled back on the reasonably clean and Copperslip approach as it deals with the galvanic interaction problem occasioned on wet days.

But above all, these are racing cars and need to be treated as such. They need proper maintenence and checks before and after every use. If you haven't got the time or skills to do this then you should employ somebody who does.

[BertBert]

LCM said:

Now, I don't want seem a boring old pedant, but isn't it ftlbs (or lbsft for young folk, or indeed Nm for those both young and scientifically trained) rather than ft/lbs? Multipying two numbers together gives a slightly different outcome from dividing one by t'other

I'm still punting for finger tight!

[nightSpirit]

I have this issue each time I fit the wheels aswell...funny thing is I only fitted the wheels to allow moving the car around the garage, 3 come off with impact gun, one won't budge.

I'll be going for the scaffolding approach I think, I tried giving the wrench a heavy smack to 'jolt' it but no dice.

[gixermark]

reminds me of when i first got my prosport.... scaffold bars and all sorts... total nightmare..

i ended up getting REALLY fine wet and dry paper, and cleaning the two surfaces... i just did this as part of pre event maintenance/spanner check.

i used a very small halfords 1/2" torque wrench.. set the fronts to 200 and the rears to ~215/220 and never had a loose nut, and they were very easy to back off too...

at the start i did wonder WTF i had bought - as it took me + 2 or 3 mates to get the wheels off !!

[double d racing]

Hi all been away so slow response but here goes my threepence worth...
1. Regularly clean the threads on the nut and hub ( checking for burrs etc )
2 Check mating surfaces of wheel and nut are clean.
3 we use a tiny tiny drop of duck oil on the hub thread each time on/off
4 if the car has been to the factory or serviced elsewhere instruct them NOT to use air guns ( unless you have same equipment )
5 when applying nut, hand tighten as far as you can to avoid cross threading and you can also feel any resistance/burring. Then finish with electric gun and torque wrench.
6 If there are continuous problems with being unable to part wheel and nut then a thorough check of all threads etc
7 If you are really concerned then loosen nuts off after every ( or nearly every session ). Do it as soon as you come in whilst all the temperatures are about the same.
8 we have ALWAYS used electric gun and have never had problems, despite what has been said.
9 Now the really sensible bit...on my car we have a false aerial. The system is that if the wheels are not correctly torqued then the safety clips are on the aerial. If they are correctly torqued then the safety clips are in. No deviation !
I realise that this may be a summary of previous comments.
Regards D D

[nightSpirit]

I got the offending nearside wheel off yesterday using the 24" breaker bar and quicklift jack arm bar. I had my long suffering wife in the car wrestling the steering wheel and applying the brakes

[double d racing]

Just goes to show what happens when you get a good woman on the job !! teeeeeeeeeeee heeeeeeeeeeeeeeee will she fit in the tool box ?

[rfairwea]

radicaltechnical said:

if you would like to receive technical bulletins, then please send me an email at [e-mail].

I sent the email but haven't received a response/confirmation. Is there anything else I need to do?

Also, is there a location to download prior bull items? I just purchased my 2007 Radical SR3 & would like to get previously issued bull items if possible.

Thank you,

Rick