Hello Forum,
This is my first post, so firstly I would like to say thank you for the hrs & hrs of reading, absorbing and getting educated by some very knowledgeable, clever and proper engineering types, in this my first ever foray in to Brit/BSA ownership, in over 45yrs of Japanese/Italian/Spanish bikes.
I have purchased a well used but lovely A50 RS, with the Devimead 750/SRM upgrade which was completed in 1997(SRM are on my doorstep here in Aberystwyth), and have just recommissioned it after 22 yrs of being sat on a hydraulic bench! It rides beautifully, and I am very impressed and smitten, so it's a keeper for sure, but just one thing that I must sort out, is the next to useless front brake..I have been acquiring parts for a TLS 8" upgrade, and have what I hope are the right front forks for the job, I think they may 69/70 A65?? Could anybody enlighten me with correct identification please? I have studied them carefully, but find no id markings ? I will then order a full kit of seals and bushes etc, for the rebuild. The lug/tongue on the leg is 2mm too wide for the groove on the TLS plate, which is odd, but I can thin this down for a snug fit. Pics attached of bike and the forks I be fitting..Thanks Iwan.
The forks are 70 triumph, not much difference in them, but the A65/A50 had a 1 degree axel offset in the axel clamps. To identify this the caps have a dimple (drilling) on the clamp and the leg to prevent you putting the wrong cap on the wrong leg. However many people have fitted the triumph legs in the last 50 years and I have yet to hear a complaint.. other than those made by our cousins accross the ocean who drive on the opposite side of the road, who complained of handling issues...
Hi Allan, fantastic, thank you very much, I did a quick search on the net and then found them, exactly as you described, I knew I have come to the right place. They are the shuttle valve type, so in theory, the internals are exactly the same as BSA, and I could order the kit from usual BSA shop, or would you recommend Triumph kit? Ta
Quote from: Allan G on 12 Jun, 2023, 14:15
The forks are 70 triumph, not much difference in them, but the A65/A50 had a 1 degree axel offset in the axel clamps. To identify this the caps have a dimple (drilling) on the clamp and the leg to prevent you putting the wrong cap on the wrong leg. However many people have fitted the triumph legs in the last 50 years and I have yet to hear a complaint.. other than those made by our cousins accross the ocean who drive on the opposite side of the road, who complained of handling issues...
Apologies for the thread hijack, but many thanks for that information Allan.
I'm in the process of building up a '69 Lightning which was (is) a basket case and came with no forks/yokes.
Would the axle offset apply o the '69 type group forks too ?
As for the OP, sounds like you've got a very nice project there, good luck with the TLS conversion.
650 or 750 upgrade is the best thing to do with a Royal Star IMHO, but that comment may well upset some people
Hi ferretjuggler,
The BSA 1° sloping front wheel wasn't applicable to all A50/65's, it was a later introduction as described by Allen. Over the years Triumph sliders have been used and people have machined them level so there's plenty of mismatching out there. Also if they have been machined level, the tell-tale dimples and a letter "A" which was stamped on the mudguard bracket will most likely remain. I have seen the angled caps fitted on the original sliders and an angled slider used with an original slider etc. Very few people outside the factory knew the reason for the 1° slope so there's been lots of previous mix ups.
The way I approach the forks, is to place them together and compare the thickness of the material as shown by the images. First set is the 1° and the second set the original standard set. Its easy to see the differences.
Most people like the original standard set up because the wheel rim sits centrally in the forks, however you'll get the front and rear wheels parallel but out of line. I have always used the standard set up without too much issue, as Allen stated the US riders were finding the bikes drifting into the other side of the road.
Best wishes...
Many thanks for that.
A bit of a pig when you're trying to compare people's badly taken photos on eBay or whatever.
I'm still on quite a learning curve when it comes to the '62 to '70 bikes, having a background of Triumph OIF bikes.
Never mind.
If I'd wanted a nice easy hobby I could have taken up stamp collecting
Quote from: Agusta MV on 12 Jun, 2023, 17:51
Hi Allan, fantastic, thank you very much, I did a quick search on the net and then found them, exactly as you described, I knew I have come to the right place. They are the shuttle valve type, so in theory, the internals are exactly the same as BSA, and I could order the kit from usual BSA shop, or would you recommend Triumph kit? Ta
It should all be the same, but if in any doubt i would order any spares as per triumph, check though to see if there are any differences between the Triumph and BSA fork stanchions, there might be a change to the taper or the length? (hopefully they will be identical)
Brilliant, thank you Allan. Wow, very interesting reading by you, Bess and Ferretjuggler(really? haha), as I initially thought the 1* offset was being referred to the Trail, but a sloping spindle, that is something that I have never come across in all my years!! Now that I have seen the photos by Bess, I can clearly see it, unbelievable solution to an odd occurrence, and does it actually work? It is strange that in the top photo of Bess's, the bottoms have the same drain screw/bolt set as mine, so are they meant to be like that, one hex bolt and flat head screw? Anyway a good study of my forks in the garage reveals they are of the none sloping type, phew, and that they measure up identical to what there is fitted in it now, so yolks should be fine. I am so grateful for all this information, and no doubt, there will be more questions coming from me...Thank you all..Iwan.