1978 Bonneville T-140V

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Once the metal retainer is in place do I need to do anything to it to make it expand or anything? I didn't do anything on the other side and it's staying in place. The caliper rebuild kit is from MAP.
 
Hi everybody! Sorry I haven't been back here in a while. I've been too busy enjoying riding my Bonneville. It will be rainy season soon and I will probably get into more tinkering on it. However, my current dillema is this. I have, for the first time, removed the exhaust pipes from the cylinder head. It was a very simple procedure. Once everything was loosened they simply slid out. Then I looked in the manual for instructions on replacing them properly. While taking them off I was cofused as to the purpose for the finned clamp that encircles the pipes where they enter the head. Then I found out about the exhaust spigot or stub that these clamps would compress the exhaust pipe onto. I seem to not have stubs. The pipes themselves slide into the head to the machined shoulder. I can see that one of them is not tight and it leaks here. Are some aftermarket pipes meant to be push-in and not utilize stubs? Is the finned clamp now just cosmetic? I don't see the stubs in the parts catalogue either. Are the pipes actually held in place by the bracket down below and the attachement of the mufflers to the frame? I had not noticed any noise coming from the leak. Should I use an exhaust cement of some type when reinstalling? Any clarification would be appreciated.
 
I haven't had the header pipes off of my '78 T140, but I believe what you have is correct. If you scroll down on THIS PAGE you will see screw-in spigots for '71 and earlier models and the spigots that convert the "PUSH IN" type cylinder heads on your '78 to accept larger diameter pipes. And yes the little brackets on the header pipes and the muffler hangar straps are all that holds things in place.

It probably wouldn't hurt to use some cement, but don't overdo it so you can take in apart later if you need to.
 
I don't know if the finned clamps you mention are standard on your bike or not, but their purpose was twofold; to hold the pipe onto the exhaust stub and draw away heat from the pipe. If no stub then they just draw away some heat.
 
I hadn't thought of that but it makes perfect sense. The less heat the better. I'm looking into adding an oil cooler for just that reason. Anyone have advice on oil coolers?
 
There are two types of cylinder head. Some are into-head fitting (like yours) and some are onto head (via a screw-in stub). The rings will help dissipate heat in both cases, but are not absolutely necessary on the into-head design.
 
Hi everybody. I can now disassemble and reassemble an Amal Mk 1 carburettor with my eyes closed. (not really, but I'm pretty good at it.) I have them both working quite well from pilot to full throttle. Someday I will meet up with someone who has one to see if mine sounds even remotely correct. One question here: in which notch should the clip be on the needle valve? One place I read the center groove and another place I read position 1 which I'm pretty sure is the top (the leanest setting). And if I have it in the wrong place but it seems to run about the same is there an advantage to having it in one position over the other?

Here I am with another slight problem which is the reason for this post. I have been riding my bike alot and get a lot of comments on it. One of the most frequent comments is "Hey, your tail light is out." Sometimes it's my brake light. Either way it's one or the other filament in the 1157 bulb. I should have bought stock in Sylvania. That's the brand they carry at the closest autoparts store. What can I do to make the bulbs last more than a few days?

I've spoken to the good folks at British Cycle supply up in Canada and they have an LED panel to replace the reflector and socket. It'll cost over $100 with shipping. That's not out of the question at the rate I'm going through bulbs. Before I do it though I was looking for any advice here.

I have put rubber grommets on all three mounting points of the tail light assembly to the fender.

I can't use the LED 1157 bulb that I paid $12.99 for. I found out after the fact that they will only work with negative ground.

After I finish here I'm headed to the garage to put another bulb in since I did in another one yesterday. I have been riding on smooth pavement 99% of the time. We don't have frost heaves here in south Florida.

Looking forward to your responses.

Frank
 
I am not the person to answer much about AMAL carbs so I'll leave that up to someone with more know-how with them.

As far as the tailight/brakelight goes.......it sounds like there is a short somewhere in the wiring. First, can you ascertain if it's the front or rear brake switch which seems to blow the bulbs? A common place for shorts would be anywhere one of the supply wires passes through a hole in metal.....such as through the fender or through the headlamp bucket. Have you removed the actual taillamp socket and looked to see if there's any loose wires behind it?
 
I'm leaning more toward vibration being the culprit. One time it will be the tail light filament that I find dangling and the next time it will be the brake light filament. The socket itself is properly wired. I have even resoldered two of the three connections to it.

If it is a brake switch that's doing it it's got to be the rear. The front one shorted and is currently removed and the wires covered. Does anyone have a spare one of those for sale? The sliding plastic pin has been welded to the plastic body of the switch. I'm going to try to fabricate another one out of some marine plastic I have. The Brit Cycle supply folks don't have the part. They can only supply one that goes on the front of the brake piston where the banjo is that prohibits putting the protective rubber boot back on. I digress.

Back to the tail lamp. I will check for a short/bare wires, but like I said my first thought was that it is vibration causing the problem.
 
I'm not being much help here, but I ride a BSA 441 single that does vibrate a lot. Your bike should be smoother than mine, but then we restrict our rides to back roads and at less than 60 mph.
The tail light bulb has never disintegrated in the 11 years and over 6000 miles I've been riding it.
However, you probably ride at higher speeds and might induce higher and constant vibration that eventually damages the bulb.
BTW, British Cycle Supply is only 45 minutes from where I live and they are indeed good folks to deal with.
 
The front one shorted and is currently removed and the wires covered. Does anyone have a spare one of those for sale? The sliding plastic pin has been welded to the plastic body of the switch. I'm going to try to fabricate another one out of some marine plastic I have. The Brit Cycle supply folks don't have the part. They can only supply one that goes on the front of the brake piston where the banjo is that prohibits putting the protective rubber boot back on.

As far as the front brake switch goes, Northern Eagle may be able to help you out. Scroll down about 1/2 way on this page for front brake stuff: http://www.northerneagle.ca/Triumph%20Control.htm
 

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