Intruder 800: One cylinder barely runs

[HansMerkl]

Hi,

Maybe some of the mechanics here can help me:

After the winter break my Suzuki Intruder 800 sputtered a lot and backfired. I followed the usual advice and did the following things:
- Check all wiring
- Replaced spark plugs
- Replaced the battery
- Took the carbs apart and cleaned them

The carb cleaning took me a few days but after reassembling the bike showed exactly the same problems (not the slightest difference). Pretty depressing after all that work... but suddenly the blinding flash of the obvious struck me: I unplugged one spark plug, started the bike and voila: The engine runs fine with only the front cylinder, but when it runs on the rear cylinder only, it idles, but as soon as I am trying to rev it up the engine will stall (no problem doing this with the front cylinder).

I have checked the spark of the rear spark plug and it looks fine (it looks the same as on the front cylinder).

To me that indicates a problem with the rear carburetor but before I take it apart AGAIN I would like to have a better idea what to look for.

Does anybody here have an idea what I should look for or any other things I should check before taking the bike apart?

Thanks in advance

Hans

[Robby]

The suzuki 800 v twin is very cold blooded, particularly on the rear cylinder.

Try richening the mixture by half turn, and just have a fiddle with the mixture screw. Make sure you note the settings its at before you fiddle.

If you have tamper proof caps on them, have a look at www.vx800.net , they have an extensive workshop area with a bit dedicated to your problem in the howtos.

[HansMerkl]

www.vx800.net is an excellent site. Thx a lot.

[Big Pete]

if you have two coils, one could be on the way out, if its a single coil its probably mixture.
____________________
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GarageOfPower.co.uk

[HansMerkl]

I think I got it.
Previously I have changed the mixture with both cylinders running. This time I unplugged the front cylinder and changed the mixture of the rear cylinder. This way I was able to get it run.
I think previously at idle speed only the front cylinder was running so it didn't make a difference what I did with the rear cylinder (it was wayyy off so small adjustments didn't help).
It seems it's a good approach to unplug one cylinder and adjust the other one while it's running alone. You can even ride the bike on one cylinder, just with half the power.
Hope nobody will tell me that this will blow some other parts

[baldy]

[HansMerkl]

As I wrote in the previous message I think I found the problem.
But it's funny: I have received so many many messages from people whose bikes had the same symptoms but the solution was completely different .