Quote from: MountaineerLarry said,

"It is clear that lots of compromises were made by Suzuki when producing the GS500. The pilot jets were clearly an easy way of meeting emissions while sacrificing cold performance."

That doesn't sound like a very big compromise. When the bike is cold, it shouldn't be expected to perform like one that is warmed up.

It seems to me that minimum emmissions indicates a clean burn. More emmissions point to incomplete combustion and wasted fuel. Where is the performance in that? I understand why a choke is needed on a cold start. Cars nowadays have a lot of technology to get the thing to run fine when cold. That would be impractical on a bike. Once the bike is warmed up, then what you want is a clean burning engine that develops maximum power. If you move the fuel/air mixture off of that standard, how is it that performance improves?

Minimum emmissions indicates not clean burn, it indicates unburnt air (oxygen)... now even a richer mix has un burnt air ... but less of it. You ahve fully burnt hydro carbons, partially burnt HC's and un burnt HC's as well as un burnt air in all IC engines. The richer the mix ... the more the first 3 and less the last one. The more O2 you have ... meaning leaner mix = hotter motor = less life in air cooled motor. Water cooled's however react much differently ... you miss by more than 1-2 jet sizes and it will run like shaZam!. Example ... 1 size larger pilot in a GS (42.5) = barely noticeable, do that on an eli 1000 40 from the stock 38 ... and nightmare. ... not just off idle where you'd expect it ... all over. Miss the thing on the lean side and similar effect. water cooleds dont adjust their temperature that well, air cooled bike will cover anyhting with less or more heat ... You really want to jet it toi being the richest possible and still run well under all weather conditions. That will be the coolest running motor that still comes up to temp and lets oil and everyhting work well. In any case, jetting with a stock setup will pretty much do that for you. No real power from 1 size jetting. Its like that 1/2 mm overbore ... no chance it will make more horses ... Its just to start afresh and erase the wear on it, same thing with jetting. You might have altitude working for you as does kerry so y'all feel you are spot on. The rest of us ... well we want to be Canadian ...
Cool.
Srinath.
:lol:

I really wish I could find a decent temp gauge to put on the bike. I rode a GS 400 for 27 years including a lot of time going real slow, up hill, on forest dirt roads. The thing was stock all around (rusty as shaZam!) and although I did occasionally fiddle with the mixture screws, it was always to get the best smooth running at idle. The engine was nearly identical to the current GS500. The old bike got about 50mpg. It never exhibited overheating, and I never saw any evidence on the plugs. Sometimes it would get a bit hot to the touch, but it never stumbled or locked up.

With the 2001 GS500, I'm getting about the same deal but the plugs are very light-not white. I just did the 7500 mile plug replacement, and the old ones looked good. Steady 75+ mpg.

If the old GS could rack up 27,000 miles I guess I'll take my chances on the new, much-improved version with the factory tune. But I still wish I could find a good temp gauge. Any ideas on that?