Rebuilding carbs. Bought a K&L rebuild kit. Obviously for a 01+ model, but I have a 2000, ie only two jets.
The needle that came with the kit is a little longer than what was in my carb originally. Since it was new, I put in the new needles from the kit... But I am starting to have second thoughts, reading all the tuning threads. As I have come to understand it, the clip position or the washers make the mix richer or leaner. Hence, if the new needle is like 5-10mm longer, no matter what, it will be way too lean and f%$k everything else up, do I have that right?
If so, I am thinking of putting the old needles back in.
here's the rejetting stats:
2000 GS500e
V&H full exhanust and K&N lunchbox
Pilot (bleeding) 40
Main Jet 50
Stock needle jets were at clip position 3 with one washer applied
Reading the rejetting matrix, it seems like my old needles should be either where they were, or two washers for a richer mix. I'd prefer maybe one washer and not overdo it between the 150 main n such.
Advice?
If your old needle looks good use it! Wrong new needle will ruin everythign. I would rise the needle (lower the clip on) from middle slot at least with 1 step (you have the adjustable needle?) or maybe with two because you have the lunchbox. Raising the needle makes mixture richer. Middle throttle is not that sensitive that you would have to play with washers in addition to clip on position!
I will get v&h exhaust in few weeks could you post a soundcheck!!!!!? I am thinking to buy lunchbox also but I am not sure if its worth it(considering the vaccuum noice is it nice??). Stock airbox will provide so good air fuel mixture for the gs that I am not sure about lunchbox.
Quote from: nurms on February 15, 2021, 11:33:51 AM
If your old needle looks good use it! Wrong new needle will ruin everythign. I would rise the needle (lower the clip on) from middle slot at least with 1 step (you have the adjustable needle?) or maybe with two because you have the lunchbox. Raising the needle makes mixture richer. Middle throttle is not that sensitive that you would have to play with washers in addition to clip on position!
I will get v&h exhaust in few weeks could you post a soundcheck!!!!!? I am thinking to buy lunchbox also but I am not sure if its worth it(considering the vaccuum noice is it nice??). Stock airbox will provide so good air fuel mixture for the gs that I am not sure about lunchbox.
The washers are much larger, move the needle more, than the little e-clip notches.
So, funny. I bought this bike non-running. But once I got the valve clearances in spec, I could get it fired up. If I rev it to mid range, it actually sounds pretty nice, even though tons of other things are wrong.
Once I finish the carb installation, I will be sure to post a video to Youtube of just the sounds. I chose to add a lunchbox because the stock airbox is so hard to get in and out it's hard to seat the carbs on the manifolds. I also chose to change it because there's already a full exhaust. Hence I was afraid it would be starved of air and never have a good mix if I didn't open up the intake.
The lunchbox is nice! You can think of it this way, how the engine would suck more air in if it is easier to push it out? Intake would remain almost exactly the same as with the stock exhaust, mixture just burns easier because there is no backwards pressure. New exhaust will tho give you some extra reserve to play with the intake!
I think I will tune my bike with the stock airbox because last summer I had to buy expensive original airfilter due to throttle cuts in max rev range in 6th gear. My HiFlo filter was letting too much air in when accelerating at high speed using max power in 6th gear. Problem was solved with original airfilter which lets less air in at max speed. That is why the lunchbox needs huge main jet compared to the original airbox, tons of air when gs is giving it all!
Lunchbox will make it much harder to tune and almost definitely will lose torque vs. stock airbox.
The reason you need a bigger jet with lunchbox is not because it has "more air". It's because it has slower air, so you have to dump more fuel into it just to keep the mixture right. It screws up the vacuum as well so the slide, needle, all don't behave as expected.
well, they seemed very common on the forum, and there was plenty of data for jet settings and carb tuning, so I went for it.
and I decided to return the original Needle jets.
Went to put the carb back on the bike yesterday and the choke slide mechanism had locked up (probably due to cleaning chemicals. I did not remove the choke valves before ultrasonic cleaning).
So, yet to replace carb, but hopeful I get to it today (kids school is closed... so we'll see...)
Quote from: struckjm on February 15, 2021, 11:05:57 AM
Rebuilding carbs. Bought a K&L rebuild kit. Obviously for a 01+ model, but I have a 2000, ie only two jets.
The needle that came with the kit is a little longer than what was in my carb originally. Since it was new, I put in the new needles from the kit... But I am starting to have second thoughts, reading all the tuning threads. As I have come to understand it, the clip position or the washers make the mix richer or leaner. Hence, if the new needle is like 5-10mm longer, no matter what, it will be way too lean and f%$k everything else up, do I have that right?
If so, I am thinking of putting the old needles back in.
here's the rejetting stats:
2000 GS500e
V&H full exhanust and K&N lunchbox
Pilot (bleeding) 40
Main Jet 50
Stock needle jets were at clip position 3 with one washer applied
Reading the rejetting matrix, it seems like my old needles should be either where they were, or two washers for a richer mix. I'd prefer maybe one washer and not overdo it between the 150 main n such.
Advice?
Non bleed 40/150 for lunch box and pipe only works with stock needle. Bleed 40 behaves like a 42.5 non bleed. Mine used to fall on its face with 42.5 at take off, but a nice revved up take off would work just fine. Too rich under 1/8th throttle except when cold as the dickens.
Remember needle is an obstruction in the emulsion tube. The main jet is the entry point for fuel into the emulsion tube.
So you've got 2 ways to send more fuel through. Make a bigger entry, or make a smaller obstruction.
The DJ of old - remember they were the oldest company to let you modify carbs with their parts - they would sell you a needle with instructions to just change your needle for theirs if you have a pipe on etc etc.
Ofcourse that got worse and more complicated with everyone and their brother making a pipe and making a filter and whatever ...
But back in the old days there was 1 setup where all you swap is the needle. BTW if you had 122 mains from DJ and their needle - you presumably could have dropped in just the needle in the bike - aka - you never needed to remove the carbs off the bike.
I had a Katana 600 that someone did that on and the bike had a Yosh pipe and it behaved very very well.
Anyway 40/150 will need stock needles. The corresponding DJ setup would be 134 DJ mains with DJ needle. I think but no idea, cos I never tried to tune that.
Cool.
Buddha.
Quote from: The Buddha on February 16, 2021, 05:30:44 PM
Quote from: struckjm on February 15, 2021, 11:05:57 AM
here's the rejetting stats:
2000 GS500e
V&H full exhanust and K&N lunchbox
Pilot (bleeding) 40
Main Jet 50
Stock needle jets were at clip position 3 with one washer applied
Advice?
Non bleed 40/150 for lunch box and pipe only works with stock needle. Bleed 40 behaves like a 42.5 non bleed. Mine used to fall on its face with 42.5 at take off, but a nice revved up take off would work just fine. Too rich under 1/8th throttle except when cold as the dickens.
Remember needle is an obstruction in the emulsion tube. The main jet is the entry point for fuel into the emulsion tube.
So you've got 2 ways to send more fuel through. Make a bigger entry, or make a smaller obstruction.
Anyway 40/150 will need stock needles. The corresponding DJ setup would be 134 DJ mains with DJ needle. I think but no idea, cos I never tried to tune that.
Cool.
Buddha.
Buddha, I could probably really use your help here. So I got the bleed 40 pilot, and 150 main. Original needle. It's 45F yesterday, I start the bike with starter fluid (wouldn't without) and this is what I get:
Start up with choke open: https://imgur.com/a/iE3wF5Y
Revving: https://imgur.com/a/MNuMZGw
There's a new post regarding this here: http://gstwins.com/gsboard/index.php/topic,73643.0.html