SXR Jetting Help

[jlane330]

BLUF: Looking for carb setting recommendations for an SXR with wet pipe and FA.

DETAILS:
Working on my '08 SXR, trying to make it run better down low. It's always been anemic on the bottom end, I just didn't realize how much until I got my RNSJ running a couple months ago. Up top, the SXR runs great. The lake is almost 2 hrs away and is at 4200ish ft elevation, so testing is limited/difficult.

The SXR is stock bottom/top end with a factory wet pipe, TBM lightweight flywheel, milled stock head (138 psi in both cylinders), Tau Ceti F/A, stock impeller, TMB intake grate and milled nozzle. The carbs are jetted per the Factory wet pipe instructions (L: 80, H: 152.5, Blowsion t-handle needles, stock 1.5 N/S, stock black spring). I've played with the pipe water screws, currently at 1/4 open on Top, closed on mid, 3/4 open on bottom, but have tried several combinations I've seen mentioned here over the last couple years without much change. The stinger has a popoff valve on the water line. I realize this ski is heavier than the RNSJ, but performance on the bottom end has got to better than this.

Earlier this week, I pulled the carbs and swapped the stock reeds for carbon tech reeds. The stock fiberglass reeds looked to be sealing fine, but a corner on each was chipped. The reeds/manifold was reinstalled with new gaskets with thin coat of Threebond, so I don't expect any vacuum leaks. I was also planning on changing the N/S to 2.0 as I thought I was getting a lean bog off idle, but am seriously questioning that now. For example, when doing a tail stand, the ski couldn't get out of the tailstand without shifting weight all the way forward...it simply didn't have the power to pull itself out. When tuning on the trailer under load, I was getting a stall/bog off idle when the throttle was snapped to WOT, so I opened up the Low speed needle, which fixed the off idle bog but seems to have made the idle rich and keep wanting to die without blipping the throttle. Upon starting, it needs throttle blips to start. Something to note, I just checked the needle settings and the LS was only 1/2 turn out while the HS was also 1/2 turn out (again, high speed seems to be running well). This is much different than the Factory pipe instructions.

I'm measuring really low pop-off pressures for some reason on both carbs using two different gauges. The measurements are very repeatable. With the stock 1.5 N/S/black spring, the pop off was at 25-26 psi. The levers were bent up slightly (.02-.03in high), so I adjusted them to level and measured 28-29 psi. This is ~10 psi low vs the Mikuni table! I've tried new genuine Mikuni 95g and 115g springs, and 2.0 N/S and all the pop-offs are low vs the Mikuni table (some are low by 5 psi, some 10+psi). So, given my popoff is already low, maybe I'm looking in the wrong place...maybe I need to increase my pop-off pressure and open the low speed needle (and possibly decrease the low speed jet)? I'm confused where to start. I don't mind trying to make changes at the lake, but it's difficult doing in on a beach in the sun, so trying to find a good starting point. Maybe the Factory pipe instructions are the right starting point...but why are my pop-offs so low vs the Mikuni tables? I've never seen this on my SuperJets.

Thank you for any/all help!

 

[wmazz]

BLUF: Looking for carb setting recommendations for an SXR with wet pipe and FA.

DETAILS:
Working on my '08 SXR, trying to make it run better down low. It's always been anemic on the bottom end,
I just didn't realize how much until I got my RNSJ running a couple months ago. Up top, the SXR runs great.
The lake is almost 2 hrs away and is at 4200ish ft elevation, so testing is limited/difficult.

The OEM Kawasaki porting creates a lag in power.

The SXR is stock bottom/top end with a factory wet pipe, TBM lightweight flywheel, milled stock head (138 psi
in both cylinders), Tau Ceti F/A, stock impeller, TMB intake grate and milled nozzle.

Standard compression is 175psi, and a milled stock head
should have 185psi or greater. I consider 185 as the max
for pump gas.

Hopefully your compression gauge is your only problem.

The carbs are jetted per the Factory wet pipe instructions (L: 80, H: 152.5, Blowsion t-handle needles, stock 1.5 N/S,
stock black spring).

For bottom end acceleration and greater overall power:
95 low
152.5 mains
1.5 seat
115gr spring
3/4 turns pilot (low) screw
1/2 to closed high speed screw

I was also planning on changing the N/S to 2.0 as I thought I was getting a lean bog off idle, but am seriously
questioning that now.

Good

When tuning on the trailer under load, I was getting a stall/bog off idle when the throttle was snapped to WOT,

There is a limit to how fast you can blip a throttle. When it is too fast
you are creating a lean spot that can kill the engine. Keeping that in
mind, does it bog while you are riding it standing up?

Acceleration is controlled by the low jet, but which spring is used
is important, not pop-off psi, or the bottom screw. It is easier to
jet a diaphragm carb to a specific spring, and treat the main jet,
low jet, hi speed screw, and pilot screw as the only circuits to
modify.

so I opened up the Low speed needle, which fixed the off idle bog but seems to have made the idle rich
and keep wanting to die without blipping the throttle.

Like I mentioned above, the screw you are adjusting is a "pilot"
screw that controls starting and idling. But there is some overlap,
and it continues to flow all the time, so there is overlap with the
mains too.

Very common for a rich pilot circuit to decrease peak rpm.

Upon starting, it needs throttle blips to start. Something to note, I just checked the needle settings and the LS
was only 1/2 turn out while the HS was also 1/2 turn out (again, high speed seems to be running well).

Your pilot screw is telling you your low jet, is rich. But the
low jet, needle and seat & spring are a combo. So for a given
spring the low jet, (and to a lesser degree) the seat are too
rich.

In this case (on the SXR SBN-I) the 1.5, 80gr, and 70 to 75
low jet is a good combo.

I'm measuring really low pop-off pressures for some reason on both carbs using two different gauges.
The measurements are very repeatable. With the stock 1.5 N/S/black spring, the pop off was at 25-26 psi.

Don't get hung up on a specific pressure! Trust the spring & seat combo
will do its job.
(1) Always test pop-off wet (I use WD-40 inside a gallon sized ziploc bag).
(2) Test the pop-off with the carbs disassembled, and then confirm
the results with the carbs assembled.
(3) Does the needle and seat or o-ring leak before pop-off?
(4) Does it pop-off and stop leaking quickly?

The levers were bent up slightly (.02-.03in high), so I adjusted them to level and measured 28-29 psi.
This is ~10 psi low vs the Mikuni table! I've tried new genuine Mikuni 95g and 115g springs, and 2.0
N/S and all the pop-offs are low vs the Mikuni table (some are low by 5 psi, some 10+psi).

The difference maybe your gauge, or your test method.
But you were getting consistent results.

So, given my pop-off is already low, maybe I'm looking in the wrong place...maybe I need to increase
my pop-off pressure and open the low speed needle (and possibly decrease the low speed jet)?
I'm confused where to start. I don't mind trying to make changes at the lake, but it's difficult doing
in on a beach in the sun, so trying to find a good starting point.

Do Not treat "pop-off" as a circuit that needs to be changed
like a hard jet. The low jet and spring are more important
than the needle and seat or pop-off psi.

Maybe the Factory pipe instructions are the right starting point...but why are my pop-offs so low vs the
Mikuni tables?

IMO a tester using an air compressor is best, but gauge
accuracy and test method will alter the specs.


Bill M.

 

[Storbeck]

I recently had a pair of sxr carbs that were doing wierd things and I found that the pop off was way lower with the carbs assembled than with the diagram cover and diaphragm removed. The little arm was sticking up too much so the diagram cover was putting pressure on the little arm. Bent them a bit and the pop off ended up a little higher even with no diagram in place but it was very consistent assembled or dissembled. This then required basically jetting from scratch again because the pop off was effectively much higher, but the end result was much better.

So, check for that. As Bill already said, but I wanted to reinforce with my recent experience.

 

[jlane330]

BLUF: Thank you so much for the replies Bill and Storbeck, very much appreciated. I'm still confused, thinking that any previous results are null in void as possibly my N/S was being held open by the levers that were bent up.

Standard compression is 175psi, and a milled stock head
should have 185psi or greater. I consider 185 as the max
for pump gas.

Hopefully your compression gauge is your only problem.

A big issue (I think) is the elevation I'm at. Everything carbureted around here, all my life, seems to run pretty rich. 4 strokes seem to handle it slightly better than 2 strokes. With the lake at 4200 ft, and my shop at 5k, compression numbers are always low. I looked back at some pics I took while testing and was seeing 145 psi (138 psi was the SJ, my mistake) on both cylinders. My SJ with a head is at 138, and the SeaDoo 787 is similar. My gauge could be a contributor as well given the volume in the hose. Anyway, the point is that none of my machines have the compression you guys are used to seeing at sea level. We are way down on power be it a chainsaw, motorcycle, car or jetski. This is where an electric car is of interest, performance, but I digress...

The OEM Kawasaki porting creates a lag in power.

Porting, hadn't considered that as a contributor for the lag in power! Great point! This ski has always been soft on the low end and then like a switch comes on strong about 1/2-3/4 throttle. I've read and reread over and over the Mikuni manuals and figured it was related to the carb settings, but perhaps it has little to do with the carbs and more to do with the porting. My SJ is smooth from idle up to full power, with a very strong bottom/mid end.

For bottom end acceleration and greater overall power:
95 low
152.5 mains
1.5 seat
115gr spring
3/4 turns pilot (low) screw
1/2 to closed high speed screw

Thanks for the jetting specs. I'll need to track down a larger pilot jet to replicate that. Currently it has the FP recommended 80 pilot. Question about the pilot...why does that need to be changed when doing a wet pipe? The pilot only really affects the idle and low (up to 3/8) throttle (I realize it still contributes at all throttle levels, but not nearly as much at faster engine speeds)...is the engine even on the pipe at lower engine speeds? Is it because the factory jetted them lean for emissions and it's simply a correction? It seems that if the stock jetting was ok, good starting and low end power, with the stock exhaust, it'd be good with the FWP. Sounds like it might in my case as you mentioned later. I guess I'm interested in knowing when the engine comes on the pipe and starts making more HP over factory exhaust, all other things being equal.

There is a limit to how fast you can blip a throttle. When it is too fast
you are creating a lean spot that can kill the engine. Keeping that in
mind, does it bog while you are riding it standing up?

Acceleration is controlled by the low jet, but which spring is used
is important, not pop-off psi, or the bottom screw. It is easier to
jet a diaphragm carb to a specific spring, and treat the main jet,
low jet, hi speed screw, and pilot screw as the only circuits to
modify.

I didn't do a good job at describing blipping the throttle. What I found while tuning on the trailer (in the water) was that it'd stumble with a moderate blip, a blip similar to something I'd expect while riding. I tuned that stumble out with the low speed needle, which affected the starting...seems too rich. Good starting/idle had the low speed ~1/8 - 1/4 turn out, but no stumbling was at 1/2 turn out. It does not bog during a blip per se, but it's not snappy or crisp while riding. After much more research yesterday, I'd say it's rich on the N/S as it continues to accelerate but slowly...not popping or stumbling. Maybe this is due to the factory porting as well? Or, maybe the N/S was being held open due to the bent levers? So many variables....

Your pilot screw is telling you your low jet, is rich. But the
low jet, needle and seat & spring are a combo. So for a given
spring the low jet, (and to a lesser degree) the seat are too
rich.

In this case (on the SXR SBN-I) the 1.5, 80gr, and 70 to 75
low jet is a good combo.

Agreed. Initially I was thinking I was getting a lean bog, but as you say, the pilot screw indicates otherwise. I'll admit, I'm afraid of running too lean, and I'm not 100% certain I can tell the difference between slightly rich and slightly lean. Looks like the stock pilot was 72.5, right in the middle of your recommendation. I'll see if I can find those and try them. My guess is that I might have to open my HS needles a little to compensate for changes down low.

Don't get hung up on a specific pressure! Trust the spring & seat combo
will do its job.
(1) Always test pop-off wet (I use WD-40 inside a gallon sized ziploc bag).
(2) Test the pop-off with the carbs disassembled, and then confirm
the results with the carbs assembled.
(3) Does the needle and seat or o-ring leak before pop-off?
(4) Does it pop-off and stop leaking quickly?

After I posted my question, I finally came across a video by John at Watcon showing pop-off of a new carb which didn't match the table, tested quite low. Last time I tried pop-off (on my old SNSJ), it matched the book perfectly. Anyway, thanks for confirming, I WAS indeed hung up on the specific pressure. What I really learned is that my levers were out of whack for some reason...bent up way more than spec. I have since adjusted them to be level.
(1) Yep, using WD-40. The ziplock bag is a great idea!
(2) I've only been testing with them disassembled. I will confirm when reassembled...I assume this confirms the lever/diaphragm isn't holding them open?
(3) Depends, sometimes it bubbles slightly right before pop-off, and sometimes it's a clean pop-off. This seems to depend on how much WD-40 I have in there. Visually, I don't see any wear indication on the tip of the needles.
(4) It pops off and then reseals at a lower pressure, usually at a 5-10psi drop.

The difference maybe your gauge, or your test method.
But you were getting consistent results.

IMO a tester using an air compressor is best, but gauge
accuracy and test method will alter the specs.

Could be, although both gauges have been reading almost identical values. At first I thought it was the gauge or set-up causing the big difference, so I built a 2nd gauge and used a bike pump instead of the air compressor. One gauge was 0-60 and the other 0-30, and yet nearly identical results using two different set-up and methods.

Do Not treat "pop-off" as a circuit that needs to be changed
like a hard jet. The low jet and spring are more important
than the needle and seat or pop-off psi.

I was definitely viewing it this way, and appreciate the correction.

I admit, I'm still confused on tuning (just when I think I'm starting to understand it). Currently, my pilot seems rich because the LS needle is closed so much to achieve a good idle. But, with the LS needle adjusted so closed, I get a lean stumble, proven because I had to open it to eliminate that stumble. If I start with the same N/S and Spring, but reduce the pilot jet, I'll need to open the LS needle to compensate for the smaller jet to get a good idle. Off idle, won't I be even more lean than before? I don't understand the fueling transition between the "low speed outlet" and the "bypass holes" as the blade opens. It seems I need a combo that will decrease idle fuel while increasing off-idle fueling. I think I've already reduced off-idle fueling by raising the pop-off pressure ~10% (by bending the lever back to flush). So, would I actually need to lower the pop-off pressure by going to the 2.0 N/S with perhaps the 95g or 115g spring to get more fuel to the bypass holes?

(1) Does the pop-off effectively help with the transition from idle to off-idle (like an accelerator pump on a Holley)?
(2) Maybe I'm running rich at part throttle and still need the smaller pilot jet. Do I test this by throttle response from part throttle? Test for loading up after extended part throttle riding?

The Mikuni manual talks about how the pilot and pop-off work together, and to try different combinations even after finding a good running combo. When trying to find an initial setup, how do I know whether to change the popoff or the pilot?

 

[jlane330]

I recently had a pair of sxr carbs that were doing wierd things and I found that the pop off was way lower with the carbs assembled than with the diagram cover and diaphragm removed. The little arm was sticking up too much so the diagram cover was putting pressure on the little arm. Bent them a bit and the pop off ended up a little higher even with no diagram in place but it was very consistent assembled or dissembled. This then required basically jetting from scratch again because the pop off was effectively much higher, but the end result was much better.

So, check for that. As Bill already said, but I wanted to reinforce with my recent experience.

Thank you for this insight. I wish I had measured mine with the diaphragms on before any adjustments, lesson learned. I'm wondering if mine was doing the same exact thing as my levers were bent up too (no idea why). Like you, I also found an increase in pop-off pressure when I bent them to level (went from 25-26 psi to 29psi). I have not tested with the diaphragms back on, but will after yours and Bill's responses. I'm wondering if the N/S wasn't being held open slightly this whole time, in which case I can't really use my previous findings for tuning, just as you state you had to start from scratch. I've seen a few people mention that they changed the N/S to 2.0 but otherwise used the Factory Pipe jetting recommendations. The issue is, they never stated if they changed the spring, and what elevation they are running. What is your setup and what did you end up with for jetting?

I'm strongly leaning towards resetting everything to the original Factory Pipe specs as a starting point and trying to tune from there. It's a pain working on the beach in 100+ deg temps, but I'd really like to get this sorted out. I'm planning on taking my tools/parts and spending the day rejetting/tuning as needed. The two SJ's I've worked on have both run excellent with a great bottom end...hoping I can get this to do similarly even knowing it weighs a lot more. Maybe it never will without porting work?

Again, THANK YOU BOTH SO MUCH! Sorry this is so long.

 

[Storbeck]

I don't want to speak for Bill but I suspect those specs he gave you were for sea level and you'll need to be leaner for your elevation.

 

[wmazz]

I don't want to speak for Bill but I suspect those specs he gave you were for sea level and you'll need to be leaner for your elevation.

They were developed in the hot desert with a corrected altitude
of 4500 to 5500 feet. Normally I would use reverse jet specs with a
main jet near ~130, but with the extra fuel you could close the high
speed screw, or turn it out further. Just depends on what runs best
for you.

A big issue (I think) is the elevation I'm at. Everything carbureted around here, all my life, seems to run pretty rich.

Is there a racetrack nearby? I like to use the web site Air Density Online
to calculate what cranking compression should be. For example,
The Havasu 95 speedway is currently 112 deg F with an uncorrected
barometer = 28.59 inHg. If we assume your head has 185psi @sealevel,
the geometric compression ratio is 12.58:1. Then convert in-hg to psi, and
multiply 12.58 x psi = cranking compression (28.59 in-hg = 14.04 psi,
12.58 x 14.04 = 176 cranking psi). You can use this to estimate
your compression while building your engine, or estimating the
compression it currently has. You might get exact results if you
could use a trapped compression ratio, but my results using
the geometric compression ratio are close, and simple.

It seems that if the stock jetting was ok, good starting and low end power, with the stock exhaust, it'd be good with the FWP.

I would agree with that. But these days most ski's already have a good
starting point established.

Is it because the factory jetted them lean for emissions and it's simply a correction?

Emission testing was performed at an idle, and there was a credit
system given to the manufactures where you gained credits for the
number of "clean engines" so that you can manufacture some dirty
engines.

So a good starting point is to increase the low jet by 1 or 2 sizes.
That will give you easier starting, improved acceleration, and a
good idle without loading up.

Currently it has the FP recommended 80 pilot. Question about the pilot...why does that need to be changed when doing a wet pipe?
The pilot only really affects the idle and low (up to 3/8) throttle (I realize it still contributes at all throttle levels, but not nearly as much
at faster engine speeds).

You could rejet the carb so that the low speed jet to a 225 if you
wanted to, and provide 100% of the fuel. But it would require a
few mods to make it usable.

I don't know why FPP chose to use an #80, It may have been a new
or different technicians idea of good jetting. I have used the same
procedure to tune the low speed and pilot circuits since we started
using test tanks in the early 1980's. An #80 would be too rich using
the idle-drop test.

I could talk and talk about this, but I believe the simplest answer
was the Mikuni Manual caused a lot of confusion about pop-off
pressure. Initially PJS (to my surprise) cut the 115gr springs that
were in the early SBN carbs to significantly lower the pop-off psi.
Back then the emphasis was on psi instead of the spring used. I
think Yamaha and Sea Doo from the mid 90's are good examples
of carbs built around a spring (not a pop-off psi).

Sounds like it might in my case as you mentioned later. I guess I'm interested in knowing when the engine comes on the pipe
and starts making more HP over factory exhaust, ..is the engine even on the pipe at lower engine speeds? all other things being
equal.

The pipe begins to effect the engine around 1/2 throttle when
the returning sound wave comes back too soon, and causes
a dip in the power. Before this dip, most FPP pipes will make
less horsepower than an engine running without a pipe.


Bill M.

I will try to add to this as time allows.

 

[bird]

You need to get your compression figured out, unless that's from the altitude(4200ft).

I have a very close setup to yours. 2011 SXR, wetpipe, FA, high comp head, lightened flywheel, and the jumper.

You're WAY TO FAT ON THE JETs. I'm at 700ft elevation and I had to jet down two sizes from the suggested Factory Pipe(SEA LEVEL).

 

[bird]

From memory, I have a 147.5 main and 77.5 low. 1.5 needle/80g spring.

In the summer humidity I turn my lows and highs in(90 degrees and 90 humidity) In the fall I turn them back out a 1/4-1/2 turn. I ride my ski into winter(Yes November-March), in Wisconsin. My jetting is good from 32 to 95 degrees, with only some turns on the screws. I have piston wash on my pistons

 

[jlane330]

First, thank you Storbeck, Bill and Bird! I have some results, went to the lake for a day trip. A lot of driving, but good to be riding.

I put the carbs to the FP specs (152.5, 80, 1.5/80g) as a starting point. HS needle was 1/2 turn, LS I started with 3/4 turn out. The other changes from last month was the new reeds, the top water screw set to 1/4 turn and the bottom set to 3/4 (mid closed). Pop-offs measured 29psi with cover off and on and the lever was adjusted to be level with the carb body. This ran pretty well, although no where near the hit of the SJ down low. It started instantly and transitioned smoothly from idle to WOT. WOT felt good, as it always had. I did adjust the bottom water screw in 1/8 turn, which didn't seem to make any difference.

Then I saw Bird's post and decided to change my pilot to the 72.5 (stockers) that I had on me. This was easier than expected on the beach as I went prepared with tools. I only changed the pilots, no other changes to needles/other components. This definitely ran better. Starting was instant, it idled well, and the low end hit was getting better. Rode it like this trying to test if it was loading up, hesitating, etc and it just ran the best it has since I've owned it (since '09). After riding a good bit, it did some funny stuff here and there...inconsistent behavior. Hmmm. Considering Bird's input on the main jet, and knowing this jet works in parallel with the needle, I figured I'd try tuning the HS needle. I put the ski on the trailer (in the water), and started doing plug chops. Houston, we have a problem. Ends up the gasket between the manifold and head pipe was blowing water into the hull when revved. It also wasn't cleanly revving from idle to WOT on the trailer. Hmmm. After some thought, decided to leave it alone until I got home, was worried about a bed head gasket or manifold gaskets.

Trying to figure out how water was coming out of that joint, I started tearing into it this evening. The three bolts were snug, but not super tight, and the gasket was absolutely disintegrated (see pic below). I hadn't realized that the Kawi FP manifold has coolant passages at that joint (none in the head pipe though). Why? The SJ is a big solid face to seal to, but not the Kawi! I pulled the manifold and the two gaskets to the cylinder were damaged, the water pressure obviously pushed the metal into the cylinder coolant passage at the bottom. They looked to sealing ok in spite of this. So, this may be why I started getting funny behavior...uncontrolled water leaking into the exhaust and exhaust gases possibly coming into the hull (likely not a significant amount, but who knows). Maybe this is why the water screws haven't seemed to make much difference. I'm tempted to weld up the manifold at that interface and machine the face flat to provide a solid sealing surface. Anyone done this? Anyone know if the exhaust manifold is easily weldable with a TIG and aluminum rod? I've welded on FP chambers before, and on my SeaDoo cast exhaust manifold and they welded fine and the repairs have held for many years.

Compression...I'm a bit of an idiot. I pulled the head tonight since the plug chops didn't go well to check for 1) blown head gasket and 2) piston wash. Thoughts on the piston wash in the pic? I'm thinking they look good. Remember, this is with a decked stock head (minimally decked, squish bands NOT machined), 152.5 mains and 1/2 open HS needle at 4200 ft elevation (oh, and 100+ deg outside). I burned over 5 gallons of fuel today for reference. The plugs are a medium to darker tan.

Back to compression, I tested it again. Both plugs out, strong battery, throttle full open and got 140 psi in each cylinder. Hmmm, why is this lower than a week ago. Well, I realized that the hose on my tester is BEFORE the check valve, so it contributes to the head volume. Just how much does it contribute? I couldn't find a syringe to measure it, so I measured the two end fittings (hose likely a bigger diameter) at ~.2" diameter. The hose is 18" long! Oh, and the o-rings on the end to seal to the head suck. If I did the math right, that's an extra 9.26 CC's of volume just in the hose/adapter! Wow! That probably explains a lot of the "low compression". I did look at the cylinders and piston skirts thru the exhaust ports...pistons look like new, zero scuffing and the cylinder walls look excellent, no scratches can be felt with a nail. Maybe it could use rings, not sure, but don't want to get into doing the top end right now. If I went that far, I'd have the cylinders ported too, a project for another time.

So, will need some gaskets. Question is, aftermarket head, reuse this one as-is, or have this one machined? Ends up my lathe can't quite swing the head over the ways, and isn't a gapbed. Bummer! So, it'd need to be sent out if machined. Recommendations on which direction to go? Want it pump gas safe (91 octane here), and not really interested in going with girdles at this time, unless absolutely necessary. I had an ADA on the SNSJ, and have an old Blowsion on the RNSJ. My SD XP stock head was machined by Rossier. All have worked fine. Also, recommendations on a good compression tester!?!

Again, thanks for any/all feedback and advice! One last thought...I'm considering changing the main jet to something a little smaller and opening the HS screw to compensate. This would give me more ability to lean it out, if needed. Not sure it needs it though given the piston wash. Feedback is MUCH appreciated.