Hey guys. I have a 91 gs500e with k&n lunch box and straight pipe exhaust with 4" baffle. Recently did a rejet of 40 pilot and 150 mains.. About 3.5 turns Runs fantastic. But since rejet I'm only getting about 90 miles before I hit reserve.. Before rejet I was getting close to 126 miles before I hit reserve.. And ideas anybody?

Don't rejet??

Just kidding...
But you should be getting more than 200 miles on a tank...so you really messed up something!

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Quote from: bsturman92 on November 02, 2014, 12:24:54 PM
Hey guys. I have a 91 gs500e with k&n lunch box and straight pipe exhaust with 4" baffle. Recently did a rejet of 40 pilot and 150 mains.. About 3.5 turns Runs fantastic. But since rejet I'm only getting about 90 miles before I hit reserve.. Before rejet I was getting close to 126 miles before I hit reserve.. And ideas anybody?

Aside from the consumption rate. .. what size tank and how full are you actually filling it?

I went 300 miles on one tank full once on my 97 with same 4.5 gal tank and stock carbs.

Fulling it up to the point where it will not hold any more gas.  And stock 4.5 gallon.. So 90 miles on 3.5 gallons. Then gotta hit reserve

150 mains might be too large, but I don't think that's the big problem. Look into doing a full tune up on the bike - spark plugs & wires, valve check, etc.

Is the air filter wet with gas ? You smelling gas when riding ?
125 was pretty bad to start with, but you should only drop to maybe 110 with the K&N and pipe.
If you're really burning it, you'd likely be very low on power.
Cool.
buddha.

Agreed, another question, coils working good?, something aint jivin. Weak compression? What are the cylinders showing?

Just working out km from miles... 90/144 ... my bike is standard carbs/exhaust but with k&n drop in. .. even at my most abusive throttle twisting. . With my 310lbs (geared up) ... I've only switched to reserve after 200km. . 237 iirc. ..
Leaking fuel somewhere or breather issue with tank and it's not really filling up properly? ...
Geez. . Even a litre bike could probably go more than 90miles on that fuel if ridden briskly?

I wonder if theres oil fuel contaminated oil?

My 48K miler went to about 125 about the time I got 48k on it. But it got there gradually. It was in the mid 50's when it had 10k miles, it dropped to the 50's when I jetted it for uni and slip on, mid 40's around 22k when I went to K&N, then to the mid and low 40's @ 35k, and down, till to about 33 mpg around the time I got 45k on it.
Cool.
Buddha.

I have 45,000 miles  on my '09...still gets around 60 MPG


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Quote from: The Buddha on November 03, 2014, 01:02:44 PM
My 48K miler went to about 125 about the time I got 48k on it. But it got there gradually. It was in the mid 50's when it had 10k miles, it dropped to the 50's when I jetted it for uni and slip on, mid 40's around 22k when I went to K&N, then to the mid and low 40's @ 35k, and down, till to about 33 mpg around the time I got 45k on it.
Cool.
Buddha.

I have 100,000 miles on my 02 GS and it still gets 60 mpg too.

I do smell strong sent if gas sometimes while riding.. I do not see any gas leaks anywhere. And I am unsure about coils. Any suggestions as to where to start?  Also to note: after the rejet I did not do a carb sync or have checked float heights. I don't know if that could have anything to do with my problem

Anybody?

Check your float height using the clear tube method - they could be causing plenty problems. If you don't have access to a carb sync tool, take it to a shop and have it done. Check spark on the plugs before messing with the coils themselves. A good strong spark on clean spark plugs that are properly gapped is what you're looking for.

Yes floats are high and overflowing.
Sorry about that.
Cool.
Buddha.

yeah, double check floats, check to make sure your petcock diaphram isnt bleeding fuel into the carb via vacuum line. make sure your gascap seal/springs are even so fuel doesnt slosh past the filler. valve lash, cam timeing

before your worry about milage make sure the tune is correct.  aftermarket filter and pipe will change airflow in and out, and as a result fuel as well.  the idea is to free up the airflow and retune the fuel to fit the new flow.  with stock cams,bores and stroke/CR burning 87octane 150 mains are about the fat side of good AFR for your filter pipe combo @sea level. altitude does come into play, unless i miss filed my mental jetting facts, higher elevations need alittle less fuel. so if everything else checks out showing over rich, might drop it a couple numbers, 145 or even 140. i dont recall many rejets of the 2 jet carbs that used really odd numbers like 147 or 142, i have seen 130-137, 140-145-150 and race apps with custom engine parts and spec's and fuel use have gone 155 up, think someone did E85 conversion on stock engine and had to start with 160's with stock filter/pipe