So after having a look at my carbs today, I had a look at the main jet. It seems that the main jets for the carbs are 107.5, which seems incredibly lean. The bike pulls great at full throttle though and no hanging idle. I'm just not sure what is going on here, and why anyone would rejet leaner, as they are jetted pretty lean from the factory anyways.

Airfilter and exhaust are both stock. The bike has been restricted to 25kW previously to meet outdated license laws here. These has since been lifted and the PO removed the restriction, which I think was the washer style between the carbs and cylinder head. AFAIK that style of restrictor does not require rejetting though.

Picture of jet in question

https://imgur.com/a/ClzDrcs

Mine was 115 when I took the carbs apart, I suspect at some point it had been restricted and the rejet was part of that. Just no one remembered to set the jets back to 125 when they removed the restriction - they remembered to destroy the pilot jet screw heads though. It ran ok on 115, but I set it back to 125 since I'm assuming Suzuki had a reason for making it 125 stock.

Its quite hard to tell what the PO(s) were thinking sometimes.

If yours is a UK bike later than '96 115 is the factory jet size.

125 was only used on the LH carb of '94 and '95 models, RH was 122.5......Don't ask me why!




Don't believe everything you read in that wiki 

That jet looks like a different series than what's right for a GS, let alone an 89-00 GS.
You sure it wasn't drilled ... after they botched up the original.
Cool.
Buddha.

Quote from: Purtsam on May 13, 2018, 03:59:14 AM
The bike pulls great at full throttle though and no hanging idle.

If it works, it works. Who cares what size it is.

One thing, it's a myth that "hanging idle" is a [direct] indication of lean running. It's an indication of the idle being set too high, which one may have done to compensate for a lean condition or clogged carbs or whatever other reason.

So I tried with two spare 122.5's I had laying around, and the pull at WOT was really bad, noticeably worse. I just put the old ones back in, and it's pulling really hard, and I can't really imagine it pulling harder than it does now, so I'm just gonna leave it, and let it be.

If it ain't broken don't fix it I guess lol

@sledge, its ashley a French spec 'UK' bike from '98 - Do you know if 115 mains was a Euro thing?

125s should really help tomorrows MOT...

Off the top of my head I dunno, but there might be something in the factory manual, the yellow one. I will dig it out and take a look when I get chance.

Ok, so according to the yellow manual carbs for the following markets......

E-O2 England
E-O4 France
E-O15 Finland
E-O21 Belgium
E-O25 Netherlands
E-O34 Italy
E-O54 Spain

Are all jetted the same and have the ID 01D30.

Ok, so according to the yellow manual carbs for the following markets......

E-O2 England
E-O4 France
E-O15 Finland
E-O21 Belgium
E-O25 Netherlands
E-O34 Italy
E-O54 Spain

Are all jetted the same and have the ID 01D30.

Ace, nice work! might dig out the 115s again then.