BST36SS "Slingshot" Carb Question

[limeex2]

I'm running gixxer 11 carbs on mine, so here's my 2 cents worth, It may only be worth 1 cent though... The needle and emulsion tubes will almost always be worn out. The nylon slides that the carb pistons slide up and down in are a trouble spot, check closely. The carbs can be tilted enough, with float height adjustments to get it were you need to be for proper running. Use NEW carb boots and a bracket really isn't ness., but for peace of mind a brkt fabricated to hook into air box brackets on the frame work well. I can not help you with jetting. I did use a dyno-jet kit, but am unsure where the tuner ended up with for jetting. I dyno all my bikes. It runs perfect and carburetes like a new bike

[TxGSrider]

OK I had a little time to mess with it this weekend. I took some of Factory Pro's website advice and lowered the float level 1mm and leaned out the O2 readings allot but it still a little rich... but allot closer. It actually is running really good. Next weekend I may try lowering it another 1/2mm and see if it cleans up the readings some more. I also found some 150 DJ mains and my O2 readings at full throttle from 7000 up are allot closer. I will keep everyone posted as I keep experimenting with the settings.

[geol]

If vacuum caps blow off (I had a GSF1200F that had this issue), your can buy little tiny vinyl vacuum caps at an auto parts store that will stay on small vacuum fittings. Rubber caps lasted about a day or two before flowing off and those that lasted longer usually cracked and leaked soon anyway. I think I bought those little vacuum caps in the "HELP" section and they were red.

[Carter Turk]

If vacuum caps blow off (I had a GSF1200F that had this issue), your can buy little tiny vinyl vacuum caps at an auto parts store that will stay on small vacuum fittings. Rubber caps lasted about a day or two before flowing off and those that lasted longer usually cracked and leaked soon anyway. I think I bought those little vacuum caps in the "HELP" section and they were red.

Never heard of anyone else mentioning this happening. Not sure why it happens, seems like a timing issue or when the starter clutch snatches at start up.
My bike doesn't seem to light on the first attempt, as if residual fuel is left in the combustion chamber. My valve guides particularly on #3 need replacement among many other things. There's a fair bit of slop on the exhaust side of the valve stem. I just bought some caps with the fussy clamps at my favorite hardware store. They stayed on, on the last ride. When one blows off it runs like sh*t. Most folks on the GS site don't have to worry about it with stock CV or older carbs.

[TxGSrider]

A little update: I replaced the DJ Emulsion tubes and needles (with a new set of DJ emulsion tubes and needles), replaced the intake tubes, and replaced all of the rest of the O-rings in the carbs that I hadn't already replaced. Now it idles really rich (I was using the 40 pilots that were in the carb when I got them). I rechecked everything and as near as I can tell everything is set correctly so I'll have to pick up some smaller pilot jets (I think they came with 32.5 or 35's, so that's what I'll try). So now I'm waiting on parts.
Good thing I have a 3 day weekend this weekend to mess with it some more...

[TxGSrider]

My pilots arrived today so I'll get them installed this nice loooong 3 day weekend and post up the final combination for anyone wanting to do conversion.

[TxGSrider]

Just an update... despite what the "Jets R Us" website says, my carbs do not use the "bleed style" pilots (the ones with the holes). I installed them and the thing ran so rich I couldn't get it to do anything so I put the 40's back in and started over on tuning. The DJ150's mains are still showing rich at full throttle from 6000/7000 to 9500 (the readings are about 9.8-10.8 .... Id like to see 11.5-12.1 in this heat and humidity). I ordered some smaller jets from Dynojet this morning which hopefully will be in before the weekend. I also ordered some "non bleed" pilots to play with.

[TxGSrider]

I played with the carbs some this weekend and to satisfy my curiosity I took out my slides that had the Dynojet restrictors installed (part of the Dynojet GSXR1100 kit) and replaced them with some that were stock. Well it sounded great revving the throttle in neutral, and they worked pretty good at WOT from low RPMs in 1st and 2nd gear. In 3rd it felt a little flat, and WOT from low RPMs in 4 and 5 caused it to bog and stutter. So lesson learned, mine doesn't like the "fast opening" of the stock slides and Dynojet knew what they were doing.
I like testing stuff like this.

[TxGSrider]

Messed with it some this weekend. It runs like a champ now, pulls smooth from any rpm.
So tuning it at 90 degrees (and humid) I kept leaning out main jets (all Dynojets) with old kits I had. I came up with the DJ needle in the 3rd position from top, 40 pilots w/2.25 turns out on the idle screw, 132 DJ mains, and lowered the float levels .6mm.
According to my Wideband, in 2nd gear on a slight up grade hill, from 7000-9500 rpms I showed a low of 10.6 to a high of 11.4 a/f. The steady state readings vary from 12.1-13.6 at various speeds and throttle positions.
I may try a leaner mains (DJ 130 or 128) in the future when the weather cools off here and take some readings to be sure I'm not too lean with more dense air.

After looking around on the web, this is around what the guys with the GSX1100G's end up with running stock exhaust and pods (they usually end up with the needle a little lower/leaner 2nd position, 37.5 pilots, and 130/132's mains)... which is a very similar engine configuration to my stock head/cam 82' gs.

[TxGSrider]

Just a little update...lowering the floats 1.5mm was too much and produced a stumble and really lean off idle/cruise (especially with the cooler weather we are having). I raised them to 15.6mm (1mm lower than the 14.6mm factory setting) and its much better.
The bad news is that I dropped my LM-2 wideband meter and it broke. Sooooo... it may be a few weeks before I can afford another one and do any more fine tuning.

[posplayr]

Just a little update...lowering the floats 1.5mm was too much and produced a stumble and really lean off idle/cruise (especially with the cooler weather we are having). I raised them to 15.6mm (1mm lower than the 14.6mm factory setting) and its much better.
The bad news is that I dropped my LM-2 wideband meter and it broke. Sooooo... it may be a few weeks before I can afford another one and do any more fine tuning.

You need a complete setup? LM-2, LMA-3(Qty 2) and wheel speed pickup, thermocouples, RPM?

[TxGSrider]

You need a complete setup? LM-2, LMA-3(Qty 2) and wheel speed pickup, thermocouples, RPM?

Actually all I need is the meter itself as I already have everything else (I bought the RPM clamp and tailpipe clamp a couple years back for tuning my ATV's)... but it looks like it costs the same for a new basic kit as it does to buy the meter by itself from Innovate.

[posplayr]

Actually all I need is the meter itself as I already have everything else (I bought the RPM clamp and tailpipe clamp a couple years back for tuning my ATV's)... but it looks like it costs the same for a new basic kit as it does to buy the meter by itself from Innovate.

Does your RPM work? For along time they did not work as they were too noisy and in fact it took me quite a while to get both RPM and SPEED to work together. Basically there was a rookie design error in the LMA-3 and something as basic in the LM-2.

[TxGSrider]

Does your RPM work? For along time they did not work as they were too noisy and in fact it took me quite a while to get both RPM and SPEED to work together. Basically there was a rookie design error in the LMA-3 and something as basic in the LM-2.

On the GS I haven't used the tach function on the LM-2. For full throttle tuning Ive been using the Factory Pro method... so I use the long hill behind my house. I get rolling in 2nd gear at about 2 grand, click record, open throttle WOT and let the motor run up to 9500... then let off and stop recording. Its pretty easy to see from the readings where I start and where I let off by the jumps on the readings.
For part throttle I have the meter zip tied to my tank bag and watch it and the tach and note the readings, along with feeling any flat spots or surges. At off idle to about 3200-3500rpm and light throttle the mixture seems to be mostly controlled by float level. Beyond that at part throttle is mostly needle height.

On the quads the Tach lead is always finicky, sometimes it will work sometimes it wont and other times it'll quit reading after the RPMs get over 6000 or so.

[Carter Turk]

Funny you're using Factory's tuning method, and running rival jet kit parts.
What do the airfilters look like? Are they the dual oval style K&N?
Did U change the O-ring on the bottom of the plastic slide glide?
Mine were all smashed and cracked.
I'm running 32.5 pilots. Stock was 30 on 1990 GSXR-11 carbs.