Series B rear ends

[Albervin]

I am in the process of returning my Rapide to more original Series B guise but am facing big problems. Number ONE is the radius of the rear guards. While the lateral curve (?) is great and matches the hinge almost mm perfect, the longitudinal curve is a disaster and has taken 2 of us nearly all day to do a preliminary fit.
The whole issue is set in stone (metal!!) by the relationship between the lifting handle and the chainguard. I was very keen to get this right and bought a very tired but unmolested "B" chainguard to set the parameters. After hours spent trying to get the guards to fit without any stresses I see the chances of fitting the bolts into the "cotton-reels" of the seat stay are minimal due to lack of clearance with the chain guard. I may have to bite the bullet and hit the beautifully painted item with a round headed mallet !!
Any input, suggestions, shortcuts, advice....... very, very, welcome. The hinge and flap were treated to a dremel, angle grinder and file......
Time for a beer!!

 

[TouringGodet]

When I fitted a NOS touring fender to my Comet, I ignored the chain guard and lined up the fender and lifting handle first, then altered the chain guard to suit.

 

[ernie]

While on the subject of Series B rear ends, is there any difference in the length of the torque arms between B and C and if not why not?

Ernie Lownger

 

[Albervin]

I looked into it as I planned this little task. "Apparently not" is the answer. If you look at a lot of pictures of Bs you will notice the angle of the H27/1AS can be quite steep due to the length of the torque arm. I would have thought this to be not the ideal geometry but nobody seems to have thought it worrying enough to act upon. Steve, the problem with B is the short(er) RFM changes all the angles of fit for a guard made to C specs. You are effectively trying to squeeze 1/2" from the radius which may not seem a lot until you try to align everything. The profile of a B chainguard is wider than a C unit and nearly all of those I have seen have either had a hammer or press taken to them or been battered by the seat stay bracket bolts. The 2 Phils certainly did not believe in wasting space. The complete opposite is my pre war Douglas which has a lot of room between components hence its very lengthy wheelbase...

 

[ernie]

Leaving aside the question of the chainguard, I agree about the angle of the H27/1AS. Because the brake cams are higher the brake rods bind on the RFM struts unless the brake levers are bent outward. It would be good to have the torque arms 3/4" shorter.

Ernie Lowinger

 

[Albervin]

Leaving aside the question of the chainguard, I agree about the angle of the H27/1AS. Because the brake cams are higher the brake rods bind on the RFM struts unless the brake levers are bent outward. It would be good to have the torque arms 3/4" shorter.

Ernie Lowinger

Ernie, I was looking at the line of the brake rods and feeling a bit worried. I am sure there is a VOC machinist out there who could make up (say) 10 pairs of short torque arms. I will put my hand up for a pair. On the other hand, maybe someone could just hack an old pair as a trial first.

 

[ernie]

Well I did ask Peter Barker if he would cos he DAMN good with stainless steel. But he done sed NOPE. Now we can get SS strip here.

http://www.metals4u.co.uk/detail.asp?cat_id=173&prd_id=3014

Then it is only a question of cutting to length and drilling a couple of holes! Waddya think?

 

[A_HRD]

OK Ernie, now you've achieved your aim and embarrassed me into replying!

For one, I would strongly advise against using 3mm stainless in this application. It is too thin - especially as this is a nominal size and it tends to really be in the region of 2.8mm. Then remove a little more for the polishing they've done and you'll probably find its not much more than 100 thou. Going down a steep driveway in reverse could buckle it - ask Jack Barker - he knows! 5mm is just a little OTT, extremely heavy and the torque clips might not fit, so 4mm (5/32) should fit the bill.

Secondly, surely 3/4 inch shorter between centres is too much? The B RFM is 1/2 inch shorter, so why would you need 3/4s shorter 'twixt centres on the torque-arm? ?

If my fingers don't glue themselves to the metal in the freezing conditions, I'll do you a one-off mock-up and send it to you for a trial....

("Thinks: Sigh, I'll never get my own restorations done at this rate... ;-) "

Peter B
Bristol, UK.