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Motorcycle Discussions => British Bikes => Topic started by: Epreon on July 31, 2022, 06:06:02 PM

Title: Triumph front wheel offset
Post by: Epreon on July 31, 2022, 06:06:02 PM
I have rebuilt the front wheel on my 1970 pre-oil in frame Triumph TR6 650 twin with new rim and spokes.

The wheel offset is supposed to be zero with the wheel sitting centrally between the forks and with the centre of the front rim in line with the axis of the steering head.

Having fitted the forks I find that the clearance between the wheel and forks differs by an average of 3.2mm between the left and right hand fork sides.

I would be greatful if anyone could let me know whether I have to correct this fault or is the small amount of out of alignment in this case acceptable?
Title: Re: Triumph front wheel offset
Post by: L.A.B. on July 31, 2022, 08:33:11 PM


Having fitted the forks I find that the clearance between the wheel and forks differs by an average of 3.2mm between the left and right hand fork sides.

As it differs by around 3.2mm then the rim is offset approximately 1.6mm which is near enough but as you built the wheel then why not move the rim 1.6mm or as near as you can get it?
Title: Re: Triumph front wheel offset
Post by: Rex on August 01, 2022, 08:33:57 AM
Yes, moving the wheel over 1.6mm would require minimal spoke adjustment. A five minute job at worst.
Title: Re: Triumph front wheel offset
Post by: Epreon on August 04, 2022, 09:03:21 PM
Thanks very much for the replies.

Having tightened the twin leading shoe brake plate on the spindle, I find my wheel is now out of alignment by only 0.39mm.  Because I am a very inexperienced wheel builder it took me hours to build up both wheels. I am not sure I would be able to correct the offset, therefore I propose to leave the alignment as it is because because it is so close to what it should be now.
Title: Re: Triumph front wheel offset
Post by: Rex on August 05, 2022, 11:29:48 AM
Mate, 0.39mm = 1/64" and that really is nothing, and if you have steel rims I surprised you can even measure accurately that degree of error over the circumference of the wheel.
That said, if if you have the noodle to build a wheel then you obviously have what it takes to correct the off-set by the required 1/128" .
Question is, why would you even try? ;)

Title: Re: Triumph front wheel offset
Post by: iansoady on August 05, 2022, 11:57:40 AM
I reckon they're good enough if they're within 1mm - .040". The kick where they're welded usually throws them out by more than this.
Title: Re: Triumph front wheel offset
Post by: cardan on August 05, 2022, 01:06:09 PM
Hi Epreon,
Good job building the wheels - it's a bit daunting for the uninitiated. Presumably the wheels are running true, but do make sure that you stress relieve the wheel and get the spoke tension uniform before you fit the tyres. It's attention to detail that will keep the wheels in good tune when you take to the road.
Cheers
Leon