QUESTION DISC BRAKE
I notice that you list the Lockheed 3125-4 Master Cylinder for sale do you have these in stock and do you know what bar size they fit?
This master cylinder is getting hard to get but we have as it happens just received some, they have literally just arrived after waiting six months and they have So yes they are in stock and they fit 7/8 bars, standard size basically.
QUESTION MASTER CYLINDER RE-LINE
Hi Roger, once again thank you all your help. My buddy that did the work lives 60 miles away so I’m going to have a go at putting it back together. I hope you don’t mind if I ask you three questions. 1 Is it all right to use dot 5 brake fluid? 2 Was the Teflon tape that RGM had around the threads just plain hardware store variety, or was it something special? 3 Perhaps I worry to much but I’m concerned that I could crack the Master cylinder casting by forcing too much tape when I tighten the sleeve up against the new washer you are sending me. Do you know how many wraps they put on it there at RGM?
Hello, no problem re questions, in answer, DOT 4 is recommended I have not tried anything else, best stick to it. The PTFE tape is just standard, I also put a little sealant in the root of the threads, just a small amount on the end of my finger, maybe equivalent of four or five match heads, we use five/six wraps, all basic and very simple, no chance of breaking it. Biggest problem is making sure it all stays clean and nothing gets blocked.
QUESTION FRONT BRAKES, DISC
Hello, looking for some help re front brakes.I have a Silk 700S that uses a single front disc with 1970's 'classic' Lockheed master cylinder and caliper (the master cylinder looks and feels much like one on a Commando I had, i.e. works but feels very wooden). I am happy to accept the general limitations of this set up, but would, if possible, like to improve the 'feel' at the lever. I see from your Catalogue that you may have two possibilities that might help? One is the cylinder re-sleeving service and the other is the Lockheed 'racing' adjustable ratio master cylinder. Can you please help with the following:
* Are these ideas in the right direction?
* Would you recommend one approach over the other?
* I read on a US www site that the adjustable ratio cylinder CP3125 comes as a '-2' and '-4' variant, with the '-4' variant no longer made, but probably more suited to a single disc? Do you have any experience of this?
Finally if you do suggest the re-sleeving work, can you advise when you expect to do this next, and how long you would need it for?
I have always quite fancied a Scot or a Silk for the engineering idiosyncrasies. You are definitely heading in the correct direction, the master cylinder/caliper ratio is a mile out. Re-sleeving is a good idea, I have done over 700 myself and sold three times that volume of kits, it is excellent. As you can imagine I never want to see a master cylinder again! Assuming your master cylinder is Lockheed they did single and twin disc versions, identified with a saw cut near the outlet, the twin disc item would of course be even worse. I still do batches of Master cylinders from time to time but pressure of work prevents any time guarantees, its not something I charge a realistic rate for so has to be done out of work time and I only do Norton ones, it takes me twice as long to do the Lockheed as have to make a sleeve, the ones I had mass produced being to long. What you have said about the adjustable racing master cylinder is correct, the single disc one you want is not readily available but that said we think we will have some in a couple of months if you can live with what you have for now and wait that long then that may be the best bet. Hope this info is helpful.
On my Mk 111 Commando, can I use a Lockheed racing caliper with my std. Lockheed 5/8" master cylinder? Or am I better advised to convert to 1/2" master cylinder, with std caliper?
Well you could go either way or use the Lockheed caliper with the re-line kit, all would work, the biggest improvement would be had from the master cylinder bore reduction. That will work very well with the standard caliper but if you use the brake very hard repeatedly on fast runs it is possible to overheat the standard caliper as it is rather enclosed.