Charlie's Shed - adapting threads

The FH kit came with a lot of original Ariel cables, most of which were pretty rusty but which still had their original adjusters and nipples. The cable layout changed with the advent of the swinging arm bikes, in that the mid-length and gearbox end adjusters moved up to the handlebars for the front brake and clutch. The thing is, most of the handlebars out there use the later 5/16" BSF adjusters, but Ariel used the earlier 1/4" adjusters to the end. Guess what? Levers with 1/4" adjusters are like hen's teeth!

So what to do? after looking at eBay for ages, and noting that Draganfly are out of stock I decided to modify what I had by sleeving the existing 5/16" thread. The issue is that putting a 1/4" thread inside a 5/16" thread leaves very little wall thickness, so the part would be weak. Here's how I set about it:

First job is to turn a bit of scrap brass to the correct OD - 5/16", and put a thread on it - these are BSF threads in these levers, by the way - so it's 5/16" x 22 tpi. Next, we can drill a hole, tapping size for 1/4" BSF, but we won't tap it yet. Next we can try it out in the lever perch and if all is well retain it with some Loctite 263 high strength thread locker:

Next job it to file the ends flush, and tap the hole. Currently I don't have a tap long enough to go all the way through, but it's long enough for the adjuster. Cut the cable slot with a hack saw and a needle file:

Job done!

FH Dry Build - Speedometer Bracket

Today's little bit of progress is this - a speedometer bracket folded up from a scrap of flat bar. 

FH Dry Build - Carburetter

 Some while back, actually in this post, I outlined the trial fit of the carburetter and the fact that the shiny new bell mouth didn't fit very well - as you see here:

Having checked the threads for damage I concluded that the undercut on the carburetter body wasn't deep enough, and/or that the last thread was not cut fully to depth since the new bell mouth did not want to screw fully on. 

I noticed that the horrible plastic one had a short length where the thread was relieved, and not wishing to set the carburetter up on a face plate and recut both the thread and the undercut, I put the bell mouth in the three jaw chuck very lightly to avoid distorting it:

I relieved the thread with some very light cuts for a few millimetres - the bell mouth fits perfectly now: