Carburetor intake insulator and o-ring damageThe original material was a form of phenolic and is mostly resin. The phenolic material is used because it is a great heat insulator and it's very good material when used with gasoline. The problem with the oring design that Honda used is that as the oring is clamped down between the carb and spacer it pushes out and breaks the lip off the old phenolic spacer. Wood of any kind would work for a while but would soon absorb the gas and start to break down. I tried to use aluminum but it didn't insulate the carb from the heat of the head and cylinder. Phenolic is still the best material and easy to find in different thicknesses. Glad to see the gaskets worked.
I found several sources for phenolic material. I had originally wanted to make it from Textolite. We used that material in generator insulation and support systems. Not sure if the textile fabric would absorb gasoline over time. Plus, I just could not score any thru my old work cronies.
The gasket is simple and fool-proof. regards, Rob Actually, it does. Keep in mind that there is another o-ring between the carb and the insulator. That o-ring maintains the constant tension.
I have resisted putting Loctite on the carb nuts because it is so damn difficult to get the nuts onto the carbs given the limited working space. Loctite would make a hard job even harder. I'll double check the nuts on the carbs. Can't hurt. Back in my formative years, my friend had a brand new '72 Commando. I was on the back. We stopped at a light and another bike pulled along side. I looked over and the rider on that bike pointed down at the engine on the Norton. I looked down and could not believe my eyes. Both carbs were loose. I would never believe in a million years that a bike would run in that condition. But it was running. We pulled over and there was only 1 nut left on each carb. He screwed them down, finger tight and we headed for home. True story. regards, Rob
First one.
Head Paper gasket Insulator O-ring Carb flange This is the same set-up that Triumph used. Only different is the inclusion of a separate intake manifold. A typical mod to Triumphs is to eliminate the insulator and use a thicker section o-ring. It has to be held in place with grease during installation. The studs/bolts are tightened only enough to squeeze the o-ring a sufficient amount and leaves an air gap between the manifold flange and the carb flange. Air is a great insulator. That would have been a possible solution if the intake hoses were long enough to reach the filters. But I don't think there would be enough engagement. regards, Rob
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
