US D shape pilot tool loan ?

Joined
May 29, 2021
Messages
18
Age
71
Location
Elkhart County Indiana
Bike
1994 ST1100
1994 1100, pair removed, TCS/ABS 78k miles
Short background, did the AdamF full clean and rejected to 128-40, set the pilots at 17/8 on the bench with .22 shell. Am very sure of that accuracy.
After a 70 mile ride at 3500 rpm / 58 mph ( should have easily kept the slides from opening and been moving all the air possible past the slow speed circuit and jet, present plug check confirmed my suspensions of the pilot screw being rich
Ground strap is charcoal ash grey,
one side of the insulator is Carmel ( experience with CV carbs on the 1200 Vmax shows that to be ) the side facing the valves
The other side is dark grey
I’m looking for all light tan or tan to clean but not white
Additionally, start shows rich compromise because the slightest added enricher will pull the idle down below 1000 rpm which is all the faster it will idle till at least half warmed up
Bottom line, rather than buy the now $200 Honda tool I will lift the carbs again unless I can connect for a tool loan
Will pay shipping both ways and rental if necessary
Thanks for reading this thread
steve
 
Right that in itself is a reason to just lift the carbs
Not having to put a lot more than needed back together before having a test ride is good resdon to attempt to get a tool
Thanks
steve
 
So in the interest of not starting a thread and then ghosting after getting replies
I got the Honda tool and went work.
There two things in particular that I feel like mentioning
Number four carb is a pain to get the tool on unless you block the throttle wide open and remove the bracket between the frame and the lug on the rear of the cylinder head, then it’s a breeze. Had no trouble with the rest
The other is that AdamF mentioned elsewhere that he tunes pilot screws using a Morgan carb tune by opening the screw till the cylinder is no longer making more vacuum.
This was intriguing and I have a carb tune ll.
I started by closing the screw and opening it half a turn at a time then quarter then eighth till the cylinder I was working on topped. Then I went back and forth in eighths till I had it just where it stopped increasing. Really works well
Interestingly the front two cylinders ended up very close in peak vacuum as did the back two but the fronts made more vacuum than the backs at the same number of turns, and the fronts went further up before they stopped, though not more than half a turn.
Did a check on the synchronization still dead on so buttoned it up.
I’ve been thru episodes like this with the cv’s on the Vmax where it seems pretty darn good and you make some extra effort and it comes out truly outstanding
Thanks for the encouragement and riding along
steve
 
Hello fellas
I’m still very satisfied with the way the bike is running and the plug coloration but
I’m still kind of baffled by the cold start instruction in the maintenance manual and videos of people wanting to sell st1100’s
My bike still does not go straight to 2000 rpm on full choke so, my question is why not?
As stated earlier my carbs are jetted at 128/40 and a previous owner deleted the pair system
The pilot screws are tuned by attaining highest cylinder vacuum as shown by a carb tune tool
If you report that your bike does this high idle at full choke at cold start will you please give the jetting and if you have functioning pair system or not
Thanks
steve
 
PS
Yes it is an enrichment system and I am confident by examination that the plungers are all fully opening and closing
Please also bring up any other factors that you feel are or could be contributory
PSS
My 1200 Vmax is jetted very similarly to the st1100 with 34 mm mikunis. It will exceed 3k on a cold start at full enrichment. By familiarity I can consistently adjust the enrichment to cold start the engine and hold it at 1500 rpm
Thanks again
steve
 
Unless they haven't been run in many weeks, my 1100s start with no choke, then I add some if needed to keep the idle smooth.
 
Last edited:
Sounds like it is to rich to me.
tnbill
Thanks for the reply
This is my theory too
Float level would play into this as well but I was very careful about setting them during reassembly of the carbs knowing that it would mean lifting the entire set back out again
Something I can do but don’t relish considering
I guess my next move will be to turn the pilot screws in 1/4 turn from current, start and ride it, check the plugs and evaluate from there
My guess is I’ll likely end up closer to 21/8 or 21/4 out rather than 2 5/8 currently
 
Ok, I decided to go to 2 turns out on the screws
I start up was much stronger and cleaner on throttle blip alone ( engine heads warm to the touch, not capable of causing a burn )
I’ll see how it acts in the morning at 36F and go for a test ride when it gets to 60F
Will do a plug check while it’s still hot and see how it goes
Thanks for following along
steve
 
I agree with the two turns out on the mixture screws. Especially having the ABS/emissions bike.
Every ST I've re-jetted to the #40 pilot doesn't like enrichment/choke. Doesn't really need it. Just press the starter button and give the throttle a little roll on, to get the engine started. I then set my Vista Cruise to maintain a higher idle speed until warmed a little. The NEP as mentioned above is a brand of throttle lock. The only time I use the choke, is when the bike sits for any length of time, such as spring time start up.

You having the ABS/emission bike, also means that you have the lazier emission camshafts. If the bike isn't in absolutely perfect running order, the 128 mains are gonna be fat. This means that the ignition system needs to be perfect, plugs, filters, etc. Also strong compression numbers. Remember that while you may have kept the rpm's low during your initial ride, the main jets will always be operating and adding to the mix regardless of throttle position. Yes, at 3800-4000 rpm, they really open up. Most Stock ABS ST's like the #40 pilot with the original #125 main. Especially those that live in very hot climates. The camshafts are holding you back. If you had a K&N filter, aftermarket mufflers, or drilled muffler baffles, then the #128 would be a better fit.

Keep an eye on the plug readings and go from there. As we are getting into the Fall season with cooler temps, she oughta run real good with all that extra fuel!
 
Hello Adam, nice to see you are still checking in
and thanks for the input
I have decided I need a throttle lock to hold a warm up ( non enriched ) idle. Not to mention the fact that this thing is simply impossible to hold at 55 mph on 2 lane highways around here no matter what gear you are in
Lazy cams eh? Something that if I’d have known about I would have skipped the mains. Not mad about it, I’ll deal with it as you suggest.
I had a chance to pick up a pair of great condition 2 brothers mufflers when I bought this bike, guess I should have taken thhh we m along with all the other stuff the seller threw in.
I’ll get a K&N, look at the stock baffles and keep tuning to the plugs.
I’m very close right now and being OCD I’ll have it dialed in before I put it up for the winter
tnbill I saw your post and I’m working on getting there before I go all the way to rejetting
Thanks for following along
steve
 
1994 1100, pair removed, TCS/ABS 78k miles
Short background, did the AdamF full clean and rejected to 128-40, set the pilots at 17/8 on the bench with .22 shell. Am very sure of that accuracy.
After a 70 mile ride at 3500 rpm / 58 mph ( should have easily kept the slides from opening and been moving all the air possible past the slow speed circuit and jet, present plug check confirmed my suspensions of the pilot screw being rich
Ground strap is charcoal ash grey,
one side of the insulator is Carmel ( experience with CV carbs on the 1200 Vmax shows that to be ) the side facing the valves
The other side is dark grey
I’m looking for all light tan or tan to clean but not white
Additionally, start shows rich compromise because the slightest added enricher will pull the idle down below 1000 rpm which is all the faster it will idle till at least half warmed up
Bottom line, rather than buy the now $200 Honda tool I will lift the carbs again unless I can connect for a tool loan
Will pay shipping both ways and rental if necessary
Thanks for reading this thread
steve
What is the AdamF full clean your talking about?
 
I kind of thought member afrymoyer who commented above might have responded to your question
Adam did probably the best photo based chronicle of removing, cleaning and reinstalling of the st1100 carbs or of any CV style carbs that I am aware of
There is a link around here somewhere, several others likely have it bookmarked and will no doubt beat me to it
 
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