New TPI bolts fit the back, but not the front

Lewis Watson

Platinum Member
I recently had my wheels powder coated so ordered a set of black TPI bolts since a number of people seem to recommend them.

I got TPI Black Tapered Longer Bolts 14x1.50 28mm ones
http://www.ebay.co.uk/itm/TPI-Black...e=STRK:MEBIDX:IT&_trksid=p2060353.m2749.l2649

Unfortunately the powder coaters returned the car with the old bolts still fitted. They said the TPI bolts fitted the back wheels but not the front. wtf?

Sure enough, when I had a go myself the bolts fitted fine on the back, but never quite tightened up at the front.

Has anyone else had a similar problem?
 

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"Never quite tightened up" ?

The only reason i can think of sitting here - is that the bottom on the bolt had somehow bottomed out, before the tapered part had grabbed the wheel. Ie: The bolts are too long. And this meant the wheel was still 'loose' - whilst the bolts were in fact effectively tight.

Why didn't they tighten up do you think ? Did you swap them all around and try fronts in the back, backs in the front etc ? (Sounds like you did).

Definitely the same thread rate etc ?
 
Once they are finger tight the old bolts feel properly tight after a few rotations with the tool. Same with the tpi bolts on the back. However, the same tpi bolt on the front is still not totally tight after more rotations than the others. Very scientific I know

I dont want to keep tightening them much more in case I break something. I don't have a torque wrench so not sure how close to "safe" they get.

As far as I can see the bolts are very similar. Ive tried measuring them (they seem to match up), Ive tried fitting the same tpi bolt on the back and front, and Ive tried swapping original bolts front and back (they swap fine).

I've got in touch with the ebay seller, they seem quite keen to help so fingers crossed.
 
Thats a good suggestion about the thread length. There seems to be a bit of rust overlap in the picture of the front thread hole.

I'll need to get the car jacked up and wheels off so I can have a proper look without worrying about scratching anything.
 
Because of the taper they do seat further into the thread, which means you are going into 'fresh' thread and more rust. The last bit there is considerable more resistance, as I recall from when I put them on my 197!
 
I had exactly the same issue on my yellow 200. I measured everything up and knew they weren't going to far through and hitting the hub.
So I basically put it down to rust and crap at the bases of the hole in the hub.
I therefore simply retapped the holes with m14 X 1.5 thread and a bit of wd40 and they fitted a treat :smile:
@Lewis Watson
 
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Thanks @Chris @Mossy it sounds like rust is the likely culprit. I dont have a tapping tool but maybe if I get the wheels off I'll be able to work the bolt in a few extra mm. Or I can maybe get a garage to have a look.
 
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Think they are M14 if you area going to tap them out

Why not use one of the old bolts and some grease, with the wheel off work the bolt in and out until it runs free
 
Thanks for the offer @Chris. After some consideration I decided to invest £15 for an M14x1.5 tap & matching wrench :shuv:, may as well do a proper job. I've already got some thread cutting oil in my shed.
 
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Re-tapping the bolt holes fixed the problem. With wheel off I was able to feel the bolt getting bogged down pretty quickly, whereas after tapping I could screw it all in with no bother.

Thanks for the help everyone.
 

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