R100/7 Vapours in Garage Doing my Head In

[Rob]

If your bowl gaskets are aged, you might want to consider replacing the floats, as well, if you haven't already.
The best way to check them is to weigh them. The material absorbs fuel over time, and become heavy. Consider them a consumable. Same goes for the braided fuel line. I replaced my lines every 3 years or so. I liked the braided stuff, it was worth the effort. Floats last much longer.

This is a new float that I still need to send off to Brad Belk....

[barryh]

I'll 2nd weighing floats having suffered with some that ended up at 16 grams.

Unless you know the weight of old floats the usual methods of setting the float levels could produce excessively high fuel levels. And in a way even more important is that both floats weigh close to the same or the carbs will never be truly balanced in terms of mixture strength.

[theswedishthing]

Good to know on the float weight front! With regards to removing them, is there a trick of any sort for getting the pin out with the carbs still mounted on the bike? If I'm just doing the gaskets and floats, I see no reason to remove them, really... That said, it's also worth noting that the bike does run well.

For now, I've separated the tank and bike and am doing a "smell test," storing the tank inside for the night and then switching them to see if there's a distinct difference in smell.

The tank itself is dry on the bottom with no signs of leakage - and it's full, so I feel like it would be pretty obvious.

Having removed some of the fuel hose sections, there is some cracking in the ends, even though they mostly remain supple; I do think this is beginning to be the likely culprit. Have gaskets and hose on order.

[PAS]

When I bought my 81 R100RT years ago (third owner) it had the cloth covered hoses and always smelled of gas until I replaced them with Gates rubber fuel line. I believe the cloth braid wicks fuel from the old hose.

[barryh]

With regards to removing them, is there a trick of any sort for getting the pin out with the carbs still mounted on the bike?

The answer to that is very carefully for fear of breaking the castings.

The pin is serrated at one end and should be removed so that the serrated end comes out first. If you look very carefully you should be able to see which end is serrated and tap it out from the other side. That will be easy on one carb and difficult on the the other as the pin will have to be pushed from the engine side of the carb. Sometimes you can get them started to move using needle nose pliers between then end of the pin and the casting.

[Chuey]

I have found the fuel line from the BMW dealer to be great. The cloth covered fuel line has not done well for me in recent years. I really do like the look of the cloth covered line but I am led to believe that it is the ethanol in the fuel that makes it go bad quickly.

The hose that runs across the bike and connects the carbs to each other is one that should not be overlooked. The air cleaner assembly will need to be loosened in order to change it.

After market fuel lines that I have tried - some worked OK and some not so well. The stuff from the BMW dealer works and fits great and is the new stuff that resists ethanol. It does not have the cloth cover.

Chuey