modelbuilder Posted December 10, 2016 Report Share Posted December 10, 2016 My TR7 V8 has had the brakes upgraded to four wheel disc brakes using Capri 2.8 callipers and discs on the front. It is also fitted with Minilights type wheels. Severe brake judder is experienced when braking hard. I do not get wheel wobble at any speed which I believe is unusual. My question is, before I set about changing the front discs and having the hubs and replacement discs machined to ensure they match, ( Stuart's suggestion ), has anybody experienced similar problems when fitting Minilights wheels? Someone has told me that they had problems with the Minilight wheels not fitting snugly onto TR7 hubs. Rodders. Quote Link to post Share on other sites
Fireman049 Posted December 10, 2016 Report Share Posted December 10, 2016 Hi Rodders ~ Could the judder be caused by a warped disc? This was the case with my MGA. Tom. Quote Link to post Share on other sites
Drewmotty Posted December 10, 2016 Report Share Posted December 10, 2016 Check the disc runout. It may be warped or not seated correctly on the hub. The hub/disc interface needs to be scrupulously clean prior to fitting. Any rust on the interface needs to be removed back to clean metal with emery cloth prior to applying a very thin smear coat of copper grease. Ensure that the wheels are clamping back to the disk face and that the wheel fixings aren't bottoming out which can happen if tube nuts are too long. Quote Link to post Share on other sites
Alec Pringle Posted December 10, 2016 Report Share Posted December 10, 2016 (edited) Hi Rodders, yes I've come across this on at least 3 Wedges, in each instance the problem lay in the centre bore . . . . . the TR7 wheels are HUBcentric, and it is absolutely essential that the wheel centre fits precisely, which all too often requires a spigot ring to be fitted . . . . . and possibly even the wheel centre bore remachining to true. It doesn't matter what you do with lug nuts, changing those to whatever version will NOT solve a hub centring problem, end of. Having said that though, you do need the correct nuts - which usually means sleeved . . . . . As an afterthought, on two of the three cars mentioned the repro 'Minilight' type wheels got skipped in due course - **** wheels, simple as that, as so many of the repro 'Minilight' fakes are . . . . . just not good enough for hubcentric fitment. Cheers Alec Edited December 10, 2016 by Alec Pringle Quote Link to post Share on other sites
modelbuilder Posted December 10, 2016 Author Report Share Posted December 10, 2016 (edited) Check the disc runout. It may be warped or not seated correctly on the hub. The hub/disc interface needs to be scrupulously clean prior to fitting. Any rust on the interface needs to be removed back to clean metal with emery cloth prior to applying a very thin smear coat of copper grease. Ensure that the wheels are clamping back to the disk face and that the wheel fixings aren't bottoming out which can happen if tube nuts are too long. Thanks, I have new discs to fit and will ensure that the mating surfaces are clean and matched but the questions really was, has anybody experience similar problems with the figment of minilights which I was led to believe can be problematic. Alec, our posts crossed and mine was sent before I saw yours. Your explanation seems highly plausible. Thanks again old son, wishing you all the best. Rodders. Edited December 10, 2016 by modelbuilder Quote Link to post Share on other sites
Alec Pringle Posted December 10, 2016 Report Share Posted December 10, 2016 Hi Rodders, any problems with the vertical mating faces of hub and wheel are likely to evidence themselves as wobble rather than judder . . . . . at least, that's been my experience. The larger the wheel diameter the more likely any imperfection in hubcentricity will be to evidence itself . . . . . again, just my experience, as you know I prefer practice to theory !! If it's any help., I have retained a full set of factory alloys which are 100% perfect functionally, as in properly tested for trueness - you're welcome to borrow those and fit your own tyres, which is a long-winded way of narrowing down the problem ! Cheers Alec Quote Link to post Share on other sites
DaveR Posted December 10, 2016 Report Share Posted December 10, 2016 Like Alec I have found the front hubs can be a poor fit on to the road wheels. You have to work the hub centre. Check the run out of the front wheels. You can taper in the leading edge of the Minilights, where they meet the centre of the hub. Thanks, Dave Quote Link to post Share on other sites
Alec Pringle Posted December 10, 2016 Report Share Posted December 10, 2016 Hi Dave, I've measured quite a few hubs, new and used, they were all spot bollocks on . . . . except for those previously chewed by inadequate wheels. The problem does not, in my experience, ever lie with the hub - assuming it is undamaged, that is. The problem lies with the aftermarket wheels . . . . . . either not designed specifically for TR7/8 fitment in the first place, or lacking appropriate spigot rings, and/or lacking appropriate nuts to match stud to wheel. Alternatively they are simply **** quality wheels, as noted previously ! Cheers Alec Quote Link to post Share on other sites
DaveR Posted December 10, 2016 Report Share Posted December 10, 2016 Hello Alec, I had the problem with the hub on a couple of 7's with standard wheels. One a car with 3,500 miles on the clock, factory fresh. Too much run out and wheel wobble. In both cases it turned out to be poor or un-finished machining of the inner part of the hub right up close to the grease cap. Maybe I was just unlikely. I agree some of aftermarket wheels are either not designed for the 7 or just ****. Either way they can give problems. Thanks, Dave Quote Link to post Share on other sites
Alec Pringle Posted December 10, 2016 Report Share Posted December 10, 2016 That's interesting Dave, evidently there were at least some problems with original hubs then . . . . . I have heard it said back in the day that quality control of the standard steel wheels was poor, as in wheels often replaced under warranty, but that the factory alloy wheel option was usually perfectly satisfactory . . . . . Cheers Alec Quote Link to post Share on other sites
REPLIC8 Posted December 10, 2016 Report Share Posted December 10, 2016 Rodney, The minilite wheels on your car used to belong to me, I sold them to the chap you bought your car from. I had them from new and fitted brand new tyres, I used them on my TR8 and then subsequently on my TR7. I never suffered any wheel wobble or brake judder on either car. When they were put on your car they had only covered about 1500 miles. If your not getting wheel wobble at any speed and it's only juddering under braking then I would suggest it's a warped disc and nothing to do with the wheels. Quote Link to post Share on other sites
Alec Pringle Posted December 10, 2016 Report Share Posted December 10, 2016 Well done that man . . . .. makes Rod's problem solving task a lot easier ! Cheers Alec Quote Link to post Share on other sites
modelbuilder Posted December 11, 2016 Author Report Share Posted December 11, 2016 Thanks everybody. As I originally thought, if there was a problem with wheels etc., I would have had some sort of wheel shimmy but as its only under breaking, it is most likely discs. I will check the run out on the present disc but will replace them anyway along with new pads and ensure thorough cleaning of the relevancy surfaces. The responses from my question were great and REPLIC8's post was most helpful. Alec, thanks for the offer of the loan of the wheels but I think now that I can source a set locally if necessary. I will get back with the results in due course. Meanwhile thanks again to one and all. Rodders. Quote Link to post Share on other sites
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