80gs1000e bogging and backfiring at higher RPMs

[Anonymous]

Well, took the 80gs1000e out for a test ride last night again now that I have the proper air box/new filter and new fuel petcock installed. Bike runs and idles nicely but when I get on it and the RPMs wind up a little right before shifting it seems to bog down a little and stutter. Tach and speedo are screwey......need to fix. I could puts around on it all day with no problem though, just when I give it the juice. I do have about a quarter size hole in the right side exhaust pipe which will get replaced soon. Could that be the problem? It is backfiring a lot on deceleration. I am planning on rebuilding the carbs and have the kits already. Any insight? Thanks

[Anonymous]

Try to wrap it.

Get some of that exhaust wrap and see if it helps. I know it won't hold, but it should last long enough for you to test it out.

[earlfor]

Re: 80gs1000e bogging and backfiring at higher RPMs

Sounds like either the carbs are badly out of synch, your main jets are varnished, your main jets are too small (should be about 120 to 122.5 for stock setup) or you could have an induction leak. Muffler leaks dont cause lean burn conditions.

Earl

Well, took the 80gs1000e out for a test ride last night again now that I have the proper air box/new filter and new fuel petcock installed. Bike runs and idles nicely but when I get on it and the RPMs wind up a little right before shifting it seems to bog down a little and stutter. Tach and speedo are screwey......need to fix. I could puts around on it all day with no problem though, just when I give it the juice. I do have about a quarter size hole in the right side exhaust pipe which will get replaced soon. Could that be the problem? It is backfiring a lot on deceleration. I am planning on rebuilding the carbs and have the kits already. Any insight? Thanks

[Anonymous]

Re: 80gs1000e bogging and backfiring at higher RPMs

Sounds like either the carbs are badly out of synch, your main jets are varnished, your main jets are too small (should be about 120 to 122.5 for stock setup) or you could have an induction leak. Muffler leaks dont cause lean burn conditions.

Earl

There is a vacume line going to the new petcock I got and a fuel line with a filter. Could a dirty filter cause the lean mixture? It looks pretty clean. Vacume line is on the carbs and seems to be tightly on, 1 line. The other line from the fuel tank is on the tank solid and connected to nothing, its by the fuel sensor (is it a breather?....its long and lays off to the side by the frame cover to drain....?). The kits I have should include new jets. I do need to synch the carbs, no idea if they are even close. Idles smooth though.[/quote]

[earlfor]

Re: 80gs1000e bogging and backfiring at higher RPMs

The vacuum line is 1/4" diameter and is connected to the petcock vacuum fitting at one end and to the vacuum fitting on #3 carb at the other end.
The fuel line is 5/16" and connects the petcock fuel fitting to the fuel "Tee" between #2 and #3 carbs.

You said "the other line from the fuel tank is on the tank solid and connected to nothing". That would have to be a breather line. There is only one vacuum line and one fuel line on the petcock and carbs, so a third line would be a vent line and should be open at one end.

A dirty fuel filter will not cause a lean mixture. As long as there is fuel, the air to fuel mixture ratio will remain the same. It could cause you to run out of fuel at high throttle settings though. :-) Some of the fuel filters (my experience) are apparently too restrictive and will not flow enough fuel for full throttle settings. You might (just to see if it makes a difference) remove the inline fuel filter and try running the bike with a straight fuel line and no filter. If the problem disappears, then the filter is the problem.

Earl



Earl[/quote]

There is a vacume line going to the new petcock I got and a fuel line with a filter. Could a dirty filter cause the lean mixture? It looks pretty clean. Vacume line is on the carbs and seems to be tightly on, 1 line. The other line from the fuel tank is on the tank solid and connected to nothing, its by the fuel sensor (is it a breather?....its long and lays off to the side by the frame cover to drain....?). The kits I have should include new jets. I do need to synch the carbs, no idea if they are even close. Idles smooth though.[/quote][/quote]