Carb Issue?

[AR_Guy]

I finally adjusted my valves, thanks Guys! The motor is still a little noisy, but that may be normal. It seems to run smoother.

Now we noticed that the #4 exhaust is not getting hot. We checked it for spark and it's fine. So I think it is a carb issue. Do I need to remove all four carbs to clean that one out? Is ther something else I should check.

I also forgot to mention last time, that my Nephew rode the bike home when we bought it. He said it was real slow. Like 35 mph top speed. I guessing the loose valves and down a cyclinder would do that.

Thanks, Again.

[Volker_P]

Well, a spark at the plug in free air does not mean that much. If the plug looks dry, it is probably carbs, if black, smell of fuel or even wet it is rather ignition (plug).
Two things to check quickly:
1. Open floater bowl release screw at the bottom of carb #4 to see if there is fuel at all.
2. Interchange spark plug with one from a running cylinder and feel #4 exhaust temperature then.
The carbs are taken out as a block and they need not to be separated for cleaning in any case. It is somewhat hard and tricky work to get them out, so for #4 only it might be worth a try to remove only the floater bowl first at installed carbs to have a look at the main jet. But you will have to separate the carbs in case the fuel connection line from #3 to #4 is blocked.

I would expect 60mph from three igniting, good cylinders, 35mph rather sounds like two of four cylinders. No reason to worry about noise at the present time. It will sound much better as soon as it runs on all four.
Before you start working, install new spark plugs if you did not do that already. It may solve your problems and if not at least you won't end up with new plugs after you got to know every bolt of your bike personally.

[AR_Guy]

Thanks for the reply. The last owner installed new plugs. I'll pull #4 and look at it to get a better idea of whats going on. I'll also try swapping the plug with another and see what happens. I've also wondered is any fuel is making it to that carb. The lines are very brittle and falling apart. I've bought some new line to replace the tank to carb line.

Thanks again. I'll try to check these things sometime this week and let you know how it's going.

[AR_Guy]

Thanks Volker!

I pulled the #4 plug, he must of dropped it, the gap was closed. I opened the gap to match the #1 plug then swapped them. Plug that was in #4 must be damaged, because now it works, but much cooler than the other three. The old #1 plug now in four, is running fine. So not a carb issue. I'll put in new plugs. That's what I get for taking other peoples work for granted.

Found another issue. The plugs were wet . . . with water. I'll have to drain the fuel from the tank. I'm sure that will solve some of our issues.

Where can I buy parts for this bike? My ignition wires are falling apart. I also need mirrors to pass inspection.

[Volker_P]

I pulled the #4 plug, he must of dropped it, the gap was closed.
...
That's what I get for taking other peoples work for granted.

Yes, that is what I am talking about. Systematic proceeding is essential to keep a motivated mind and to save your money for the things you really need.
Just imagine you had torn apart the carbs, bought a carb set etc., still no success before finding out about that.

Drain also the carb bowls and use the old fuel later or in a car. Ignition cables are a good idea, too. At the latest when they get a bit humid, porous cables will cause trouble.
I can't help you with parts, but you should find several hints to mail-order firms in this forum (e.g. Ibsen provided some links). But mirrors should be quite universal for japanese cycles, except Yamaha has a left/right thread concept. And a nearby garage may have ignition cables at correct diameter that you can cut according to the old ones.