What's up GSTwin? I may be making a comeback here, sold my '94 GSXR750 as it was ready to self destruct electrically. Now my truck needs a buncha new stuff because of a Florida style unintentional baja excursion... so motorcycle fund has been drained back to GS500 prices. Oh darn 

Anyways, I dig the F model, I always drooled over it when I was riding my naked '93. Do drag bars fit a faired GS? And how does the newer 3 circuit carb compare to the older 2 circuit? Just trying to see what the advantages of the newer ones bring 

Don't forget the oil cooler (that wasn't added because of the fairing) 

My Sexy Beoch!

I had a 97 GS that I bought new and put about 80k miles on before it was totaled and replaced with my current 02 GS.  After the insurance was finally settled I bought the 97 back and fixed it up so I had a chance to run both for a while.  The 02 with the 3 circuit carbs was stronger and more flexible thru the mid range and would pull smoothly from lower rpm's making it much more enjoyable for everyday riding about.  But that old 97 with 80k on the clock still pulled stronger on the top end than the almost new 02, seemed to me there must have been a cam change too for that difference but I could never determine that for a fact.  Both bikes were completely stock except for a 15T front sprocket I ran on the 97, no carb mods to either.  The 3 circuit carbs started with the 01-02 naked GSs, 89-00 were 2 circuit.

The 3 circuit carbs are better than the 2 only if left un touched. Once you jet the 2 circuit, there is nothing separating the 2. I have a 96 with the 3's off an 06 in it, but also ran it with the 2's before that ...
Maybe the 04+ ignition system has a part to play in that ... 

The needle in the 3 circuit carbs is IMHO the dumbest thing they did ... even worse than the savage carb that has a screwdown plate over the needle ... classic case of fixing what wasn't broken, and ignoring the 100 things that were, and of course making it worse where they could.

Oil cooler -  That was 1 they fixed that was actually somethign good.

Cool.
Buddha.

Well, I may sound stupid, but was the oil cooler really necessary? For example, look at gsJack's 100k+ bike, still running strong, never seen one... But the cooler makes the bike reach its ideal operating (oil) temp later after each cold start, and that far-from-ideal temp is responsible for a whole lot of (cylinder) wear. Now I'm quite sure I don't see the obvious here, so I'd appreciate if someone could point me in the right direction

Quote from: Atesz792 on December 23, 2013, 05:58:09 PM
Well, I may sound stupid, but was the oil cooler really necessary? For example, look at gsJack's 100k+ bike, still running strong, never seen one... But the cooler makes the bike reach its ideal operating (oil) temp later after each cold start, and that far-from-ideal temp is responsible for a whole lot of (cylinder) wear. Now I'm quite sure I don't see the obvious here, so I'd appreciate if someone could point me in the right direction

Oil cooler may be useful if you were sitting in traffic for hours ...
Or if they had made the motor to better tolerances than a 1435 horse drawn buggy ... I am in fact supprised a buggy whip doesn't come standard with the GS ...

Cool.
Buddha.

Addidas, always loved Suzi.. so clean  You actually sold me the fender and gas cap I had on my '93 

Buddha, so the 2 circuits are better than the newer carbs? Whichever year range I buy is going to get straight piped, lunch boxed and rejetted. I really like the F so how much of a difference is it between the F and older E's?


And on that note, would people actually trade older 2's for newer 3's?

Miss my '93 :/ Maybe some of you guys recognize it, I was a bit of a picture whore




[attachment deleted by admin]

Quote from: Atesz792 on December 23, 2013, 05:58:09 PM
Well, I may sound stupid, but was the oil cooler really necessary? For example, look at gsJack's 100k+ bike, still running strong, never seen one... But the cooler makes the bike reach its ideal operating (oil) temp later after each cold start, and that far-from-ideal temp is responsible for a whole lot of (cylinder) wear. Now I'm quite sure I don't see the obvious here, so I'd appreciate if someone could point me in the right direction

Heat is the Nemesis of an air cooled engine, and going on that pretense, hot oil is thin oil. So keeping oil cool is beneficial to engine life, but not a requirement. Contrary to popular belief, motor oil does not get thicker as it warms up.

Quote from: The Buddha on December 23, 2013, 05:21:16 PM
The 3 circuit carbs are better than the 2 only if left un touched. Once you jet the 2 circuit, there is nothing separating the 2. I have a 96 with the 3's off an 06 in it, but also ran it with the 2's before that ...
Cool.
Buddha.

They did that with cars too decade ago, many of the lower priced models had 2 circuit carbs and they put bigger jets in the low and high speed circuits so the richer mix would overlap and cover for the missing mid range jets.  That was decades ago before the EPA and back when you could get 3 gallons of gas for a buck.  Seems when members come here with low gas mileage problems they always have re-jetted carbs.  I don't doubt you can make a 2 circuit run as well or almost as well as a 3 circuit one but I'll take 3 circuit ones myself that get 60 mpg or better overall for 100k miles that run well.

Quote from: Suzuki Stevo on December 23, 2013, 06:35:16 PM
Heat is the Nemesis of an air cooled engine, and going on that pretense, hot oil is thin oil. So keeping oil cool is beneficial to engine life, but not a requirement. Contrary to popular belief, motor oil does not get thicker as it warms up.

Oil needs to be hot enough as well as not too hot for good performance and long engine and oil life.  Water in the oil is a natural byproduct of internal combustion and common oils begin to breakdown above 250F so it's best to keep it above 212F to boil off the water and below 250F or so to slow breakdown.

One of the first things I noticed about the GS was that it ran cooler than my previous Hondas did that were all air cooled too and ran noticeably hotter after long high speed runs than the GS.  No doubt riders that get bogged down in heavy traffic for long times would benefit from the cooler on the GS but I avoid heavy traffic like the plague heading for the boonies quickly when going riding.  I prefer no oil cooler on the GS for my usage but did put one on a hot running CB750 years ago that extended it's life.

Quote from: gsJack on December 23, 2013, 08:11:10 PMit's best to keep it above 212F to boil off the water

Does oil really need to get to waters boiling point for water to evaporate from it?

Quote from: Suzuki Stevo on December 24, 2013, 12:13:17 PM

Quote from: gsJack on December 23, 2013, 08:11:10 PMit's best to keep it above 212F to boil off the water

Does oil really need to get to waters boiling point for water to evaporate from it?

I don't think so since water evaporates at room temperature if the humidity is low enough to allow it like less than 100%.

The question needs to be two parts. One being the oil cooler and a separate question on the 2.vs. 3 jet carbs.

While the oil cooler is 2004+ only, photos of naked ones sold outside the USA do not show the oil cooler. So that means the oil cooler is there for the fairing or something to do with USA emissions and keeping the engine colder.

The 3 jet carbs started in 2001. Since they can be puts on any gs500 motor, you need to address thee pros and cons separate from the oil cooler issue. 2001-2002 had 3 jet carbs and no oil cooler.

Also note that in 2004 there was a lot of emissions crap added which is another issue to discuss when asking if newer motors are better than old.

Quote from: adidasguy on December 24, 2013, 02:36:47 PMI don't think so since water evaporates at room temperature if the humidity is low enough to allow it like less than 100%.

The question came to me as I drank my morning coffee.......

The oil cooler means nothing to me honestly, in my riding its totally irrelevant being 70% 55mph roads, the rest in regular city, no bumper to bumper.

My main questions revolve around the 3 circuit carbs and what not. Will the bike make more, less, or equal power to the 2 circuits when rejetted for a slip on and lunch box? And what emission stuff was added? All my knowledge is 2 circuit based. I really want an F but want to know what extra complexity I'm getting myself into possibly

The Buddha mentioned earlier that with stock jetting the 3-jet carbs will perform better; resulting in a smoother power delivery and transition regions.  When properly jetted, the performance is probably pretty similar when everything else is the same.

The "emissions stuff" is known as the PAIR system; this is driven from the vacuum line and routes fresh air into the exhaust headers, essentially pushing in oxygen so that the carbon-monoxide can form carbon-dioxide and any unburned fuel can be combusted before the muffler.

Thanks for the comments on the oil cooler, guys. As I rarely see bumper to bumper traffic, it may not be that important, but I think I'll just live with it.

2 vs 3 circuit carbs once you tune them are almost indistinguishable from the way they ride, atleast on a 89-00 bike.
But one thing I'll say about 3 circuit carbs - their floats dont drift. Al all, I've never found a 01+ that had floats high ...
89-00 every other year you'd atleast have to check them if not outright adjust em.
Cool.
Buddha.