Honda-SOHC
SOHC.co.uk Forums => CB350/400 => Topic started by: Mikep328 on September 08, 2023, 06:18:04 AM
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I want to verify that the correct tappet clearance is, indeed, .005mm/.002" as shown in the shop manual. I have never seen a tappet clearance that small and want to verify folks experienced with these engines that it is not a typo!
Re gauge- synching the carbs: Page 6 of the shop manual states that to adjust synchronization, first turn the throttle stop screw so that the clearance between the throttle lever and stay is 56mm. Is that normally done or is sync more often performed at idle or some other specific RPM?
The bike is running great overall and idles nicely at 1200 RPM but there is some roughness at constant slight throttle opening, as in slow town traffic where the throttle is at maybe 1500-1800 in low gear. This was very apparent/annoying in Bristol yesterday. >:( It also still does not take opening the throttle quickly as well as I think it should. I figure the mixture screws need more attention and/or my bench sync was not as good as I thought it was. ::)
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Tappet clearance is 0.05mm on the 400.
I don't know too much about the set up on a 400 but, a expert will be along soon
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'Ere Trig, did you miss out a zero in your reply???
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Nope, Mike has an extra zero ;)
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Just looked it up or 0.002in if you are old school
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Yes, I typoed an extra "0" in my message. So for those that work on these engines regularly - that clearance (as stated in the manual), .05mm/.002" IS CORRECT? In handling that thickness feeler gauge, it seems like pretty much "no clearance!" :)
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Yes, I typoed an extra "0" in my message. So for those that work on these engines regularly - that clearance (as stated in the manual), .05mm/.002" IS CORRECT? In handling that thickness feeler gauge, it seems like pretty much "no clearance!" :)
It is correct in the manual. All the rest: 500, 550, 750 SOHC are 0.08mm on the exhaust and 0.05mm on the inlet ;)
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"The bike is running great overall and idles nicely at 1200 RPM but there is some roughness at constant slight throttle opening, as in slow town traffic where the throttle is at maybe 1500-1800 in low gear. This was very apparent/annoying in Bristol yesterday. >:( It also still does not take opening the throttle quickly as well as I think it should. I figure the mixture screws need more attention and/or my bench sync was not as good as I thought it was. ::)"
Try it with the idle circuit air adjustment screws moved in 1/8 to 1/4 from where they are now, this to make is slightly richer as it progresses along the idle circuit metering.
These "idle" circuit control the low speed mixture primarily, but also with significant impact on how the carbs get into mainjet operational range, too weak here will make it start to fall flat on it's face (going temporarily lean) as it tries to get a smooth increase onto fully running main jet. They are very accurate in the amount of shift needed to refine that relationship, but ultimately very smooth and linear when set correctly.
If you can't get them smooth within decent adjustment range, it's nearly always how clean the low speed air and fuel jets/holes/flow components are.
Absolutely scrupulously clean and they work impeccably, any impairment and you'll chase yourself round and round trying to get them to work well and without throttle glitches.
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Yes, I typoed an extra "0" in my message. So for those that work on these engines regularly - that clearance (as stated in the manual), .05mm/.002" IS CORRECT? In handling that thickness feeler gauge, it seems like pretty much "no clearance!" :)
Compared to old push rod cars the valve clearances are imho relatively small. When I adjusted mine I used feeler strip and made sure that the strip was not pinched but just free to move when pulled. As usual tightening the lock nut would sometimes pinch the strip so I would back off the screw & start again. Worth getting it right for sure.
I do not know what work done on the carbs by yourself or the PO, as K2-K6 states they need to be ultra clean to run correctly prefferably using original brassware to run smoothly as well as the correct float levels. Clean fresh petrol & an intact strainer on the Petcock a must.
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I disassembled the carbs/cleaned all parts thoroughly. I reassembled with original brass, set the float levels, and installed new (NJ) Orings and bench-synced the carbs. On the bike with engine running each mixture screw functions properly, changing the idle as it is screwed in/out so I don't believe there is any issue with clogged passages, etc. I'll richen the mixture slightly, as suggested.
I'll check the tappet clearance/adjust if needed - it was allegedly set properly by the shop tech prior to my purchase... ;)
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Just looked it up or 0.002in if you are old school
Oops!! Old school, yes. Dippy old git, I guess so. Just as an aside, in case you are wondering why my brain is addled, am in the process of building a model railway layout, and when purchasing the timber I gave him the size I wanted and he replied "Oh, you mean 2" x 2" ". Yes I replied, what lengths is it supplied in, "!.8 metre or 2.4 metre" was the answer. Ho Hum.
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But timber is always sold in metric lengths of english width and height
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Plywood is advertised in metric yet it still measures exactly 8'*4'.
Sent from my Pixel 7 Pro using Tapatalk
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Wheels & tyres are virtually all in imperial for diameter, with the rest of it metric and % too. A right old mish mash.
Bicycles too, but with 700 series (was just road bikes in continental Europe) as completely metric and the rest inches dia, except 700 has now been labelled 29" for mountain bikes ::) all a bit nuts.
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Plywood is actualy 1440x1220 which just happens to be 8 x 4
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Most confusing thing in my currebt trade of HGV is up to 32 ton is english ton over 32 is metric tonne and 1,000 kg is not a ton
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This is certainly a drawn out affair. The transition from imperial to metric. My very first job on leaving school at 16 was working in a timber yard. After a shipment of timber to the islands the bings were all mixed lengths so first job was to sort all the timber into the correct lengths - 3.0, 3.3, 3.6m etc going up to 6.0m. It was great I very quickly learned my metric. Of course we always still referred to a 6 x 2” or 8 x 2” or whatever. So customer would come in and it would be marked as 2 x 4.8m x 6 x 2” rpos.
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About 20 years ago (?) they tried to force the TV & Monitor market to move metric. It failed miserably and screen diagonals still are measured in imperial.....
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I disassembled the carbs/cleaned all parts thoroughly. I reassembled with original brass, set the float levels, and installed new (NJ) Orings and bench-synced the carbs. On the bike with engine running each mixture screw functions properly, changing the idle as it is screwed in/out so I don't believe there is any issue with clogged passages, etc. I'll richen the mixture slightly, as suggested.
I'll check the tappet clearance/adjust if needed - it was allegedly set properly by the shop tech prior to my purchase... ;)
Something that may help in details. Often the great wide opinion out in internet-land is that the idle airscrew simply changes absolute mixture, when in reality these design change the "slope" of mixture leading up from lowest rpm to link into main jet response territory, which can be much further up in influence than many appreciate.
Thinking of a simple way to express it, thoughts like the following to expand a visual representation of them:- if you had a ladder to reach a second floor window of your house, you'd likely extend it to comfortably reach the sill, while leaving it at a decent angle for you to climb. Too steep and you risk it falling outward :o too shallow and you risk it sliding down the wall in the opposite to before.
The airscrew adjusts both reach and slope to get the ladder to let you comfortably reach the window safely. If the ladder is too long to get into range, that would be the pilot jet too big and not let you get down below the guttering, too short and no chance of reaching the window the pilot jet being too small.
With all passages clean and correct brassware, then it should allow you to trim that mixture slope until it attaches meeting all the requirements in blending into the mainjet lower reaches and not give any discernible flat responses, rich or lean. It doesn't matter exactly where the screws end up (within reasonable amount of turns out range) but it will calibrate your carb, your airflow, your airfilter, at your altitude to bespoke tune the idle circuits as Honda and Keihin designed it.
If you live in a bungalow, you're going to be mystified by this ;D
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Went out today and checked the tappet clearance - they were .003"+ so I reset them all to .002" Then I synced the carbs with a gauge set after first calibrating the set so that all gauges read the same when attached to the same cylinder. I had bench-synced the carbs a few weeks ago and was pleased to see that they all cylinders were within a needle's width of each other. I tweaked them so they read exactly the same though I doubt that a needle-width difference matters.
I richened the mixture by 1/8 turn on each carb but it was raining so didn't take the bike out to evaluate the change. In the parking garage it accepted a quick throttle movement from idle with less hesitation than previously.
One thing that I was NOT happy about - when I started the bike from cold there was visible smoke from the exhaust though it seemed to disappear after it warmed up. Couldn't really tell the color but it smelled oily to me. However, the spark plugs all look good color-wise with no sign of oil or fuel fouling. My wife was behind me on her bike riding to Bristol the other day and she didn't mention seeing any smoke from mine. I hadn't asked her to look for it but I'm sure she would have said something about it had she seen any smoke. In any case, further evaluation is in order.
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It may have been that you had just richened the mixture or it could be worn valve guides.
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If it's a relatively small amount of smoke when cold I would not worry about it unless you start using oil in any quantity.
I have found that older engines often give some smoke on start up sometimes due to oil that has found its way past valve guides whilst standing overnight.
Easy to panic and think the worst,
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Went out today and checked the tappet clearance - they were .003"+ so I reset them all to .002" Then I synced the carbs with a gauge set after first calibrating the set so that all gauges read the same when attached to the same cylinder. I had bench-synced the carbs a few weeks ago and was pleased to see that they all cylinders were within a needle's width of each other. I tweaked them so they read exactly the same though I doubt that a needle-width difference matters.
I richened the mixture by 1/8 turn on each carb but it was raining so didn't take the bike out to evaluate the change. In the parking garage it accepted a quick throttle movement from idle with less hesitation than previously.
One thing that I was NOT happy about - when I started the bike from cold there was visible smoke from the exhaust though it seemed to disappear after it warmed up. Couldn't really tell the color but it smelled oily to me. However, the spark plugs all look good color-wise with no sign of oil or fuel fouling. My wife was behind me on her bike riding to Bristol the other day and she didn't mention seeing any smoke from mine. I hadn't asked her to look for it but I'm sure she would have said something about it had she seen any smoke. In any case, further evaluation is in order.
You mention that it was raining when you started the bike, meaning the air was quite moist, likely as not, it was steam from the condensation gathering in a cold exhaust. In my nearly days, this cost me a fortune in replacement exhausts (CB750), as I used it for riding to and from work in all weathers, 5 miles each way so did not get hot. As much as possible nowadays I do not start the 400 unless I'm going for a long enough ride to get its really hot. I'm still using the genuine Honda system that I fitted in 2006. If you say that someone following you did not see any blue smoke and it's not using oil between changes, I think I would just ride it. Stay safe. Mike.
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Thanks Trick! I asked my wife specifically today if she had seen any smoke at all from my 400 when she was following me on her motorbike and she replied, "absolutely not!" So now my plan is to NOT worry about it!
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We went out on a ride of around 30 miles today. There was a substantial improvement in how the engine would accept opening the throttle so richening the air screws by 1/8 turn definitely helped. I still have a rough spot - stutter - at around 1800-2000 RPM which continues to make in-town slow speed running at that RPM range a bit annoying. I'd like to get rid of that...
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Encouraging that there's improvement, always feels good getting progress too.
Do you know where you've now got the airscrews set at, absolute turns out from closed in other words ?
Have you gapped the spark plugs to maximum ? If so, then try them set tight to minimum specification gap to try it like that.
It maybe you'll need to lift the needles by one notch to get the fuelling just slightly richer at that problem point, getting the idle and main to attach together smoothly being the aim, to then give that linear response you're after.
Neither the idle tweak or needle lift change the overall jetting, but both tickle it up just a small amount to try and optimise around that shift point.
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I should have checked to see how many turns out each screw is now but I didn't. I started out with them at 2 and adjusted them individually to Max RPM/ then drop 100 RPM so don't know the current settings. But I'll check when I'm at the bike later this week.
I pulled the plugs and adjusted the gaps to .028" the other day. The plugs looked good color wise but they are not new plugs - center electrodes edges are not sharp like new ones. I've been meaning to install a new set. ;) I was trying to find NGK D8ESL - which are in the engine - but they don't seem to be available so I guess the DR8ESL is the one?
I'd rather not pull/disassemble the carbs again but needle height may need to be changed. FWIW, my BMW R1200RS had the same sort of stutter at a similar RPM range that was also annoying at low speed, trundling through town. It was cured with the installation of an aftermarket electronic device (forgot the name) that "fooled" the computer into enriching the mixture at low RPM. So pulling the carbs/raising the needles might be required... :(
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Understand not wanting to pull carbs off again ;D especially as you seem to be so very close to getting them exactly how you want.
There maybe a little room to tweak the airscrews again to just squeeze it a little more into range. They are a very precise carburettor, with just tiny little refinements needed to get them on song.
Something from the later PD carb instructions from Honda manual I think is useful, to go through setup and then record exactly where they are as result of this, to then act as baseline for all those parts in situ on that bike.
Something the 400 is affected by with it's modest torque, is that if you open the throttle and it can't easily increase rpm, it then prompts the rider to open more the throttle, which reduces the vacuum under the slide and results in going even leaner momentarily. The obvious stumble a result of this.
I feel it's correct to run as lean as practically possible as it just reduces unburnt fuel excess washing into engine oil. But there's a need to get enough in there to get the revs rising smoothly and up onto the main jetting phase without bogging it down into that annoying glitch.
Sounds very close, hopefully it'll give you what you need with a little more adjustment.
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[quote author=Bryanj link=topic=29801.msg288162#msg288162 date=1694197864]
Plywood is actualy 1440x1220 which just happens to be 8 x 4
[/quote]
Ahem 2440 or 2438.4 if you really want to a pedant like me :)
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I was having a bad day
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Wonder what they do with all those 1.6mm saved all around the world ;D ;D
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Wonder what they do with all those 1.6mm saved all around the world ;D ;D
Probably used to make MDF.
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;D
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Wonder what they do with all those 1.6mm saved all around the world ;D ;D
Probably used to make MDF.
Toothpicks
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No you lot, thats the plinters in yer fingers!
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Tomorrow, in hopes of eliminating that off-idle stutter, I'll try turning the airscrews in another 1/8 turn and also replace the spark plugs. I couldn't find non-resistor NGKs but did find non-resistor Densos. I can't imagine new plugs will fix the stutter but I wanted to replace them anyway.
I have some other thoughts re stutter elimination but I'll wait to see how the above works first.
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That’s a good move on its own Mike, getting rid of NGK plugs and fitting Denso. To many fakes/faulty plugs about.
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New plugs/airscrew adjustment did nothing to reduce the stuttering. I didn't take my timing light when I walked to the garage since I had checked the timing and it was spot on several weeks ago. But what I want to do now is use the timing light to see if each cylinder is getting regular/consistent spark from the coils in that RPM range. The coils/plug wires are new from DSS, installed in '22 per the receipts.. It also has a DSS electronic ignition installed at the same time. I don't expect to find a problem with those items but I have had strange problems with aftermarket e-ignitions on motorcycles in the past...;)
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New plugs/airscrew adjustment did nothing to reduce the stuttering. I didn't take my timing light when I walked to the garage since I had checked the timing and it was spot on several weeks ago. But what I want to do now is use the timing light to see if each cylinder is getting regular/consistent spark from the coils in that RPM range. The coils/plug wires are new from DSS, installed in '22 per the receipts.. It also has a DSS electronic ignition installed at the same time. I don't expect to find a problem with those items but I have had strange problems with aftermarket e-ignitions on motorcycles in the past...;)
Can you adjust both 1-4 & 2-3 on your system or is it just one adjustment?
On my Dyna I have both it took quite a while to get both spot on.
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"Can you adjust both 1-4 & 2-3 on your system or is it just one adjustment?"
Just one adjustment. The relationship between the timing of 1/4 and 2/3 cylinders is fixed. TBH, and this might sound weird, I would have preferred that the bike had the OEM ignition system rather than an e-ignition.
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Might be worth checking both anyway to see if they match.
At the moment my 500 will retain points until I am happy with the way it runs - then I might fit the Electronic one I bought from Bryan.
There is a lot to be said for roadside fixes that points can accomodate. That said points were a pain on older cars.
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Interesting to see if tge ignition check turns up anything unexpected. They are usually reliable though.
A thought, are you running on E 10 fuel ? as that may influence your jetting and may push you up on needle position to regain parity.
Also can be worth a try as it's a quick-ish change, drop the plug gap to 23 thou to see if that has any response or verifiable shift in the effect you are getting.
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Thanks, I changed the gap on the old plugs to .025" before replacing with the new plugs, which I gapped at .030." There was no difference in operation. After doing that I checked all the air mixture screws for the position they were in after "optimizing" them last week. Cyls 2,3 and 4 were around 1 1/2 turns out. But cyl 1 was only 1/2 turn out. If the screw was bottomed, that cylinder would cut out completely but from about 1/2 turn and beyond there was no change in RPM or smoothness. So despite disassembly/cleaning, it appears there is still some obstruction in that carb's idle circuit. :(
Fuel is E10.
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Agree that the question mark over that single idle circuit is probably going to cause you more work :-\
Hard to get an clear evaluation without containing that really, unfortunately.
E-10 has approx 10% more oxygen content. So 10% of 10% E gives roughly 1% increases in oxygen to make it run a small amount lean, in comparison to it's original factory setup.
With that in mind, and while the carbs are off, it could be valid to then lift needles in targeting this overall review of running competently. Depends on your personal assessment of it though.
If that were to be run like that it would likely still be contained within an air screw tweak. Just that it'd fatten up the mid to low response to help you out there.
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Today I'm going to check the spark delivery on the 4 cylinders and also check/verify that the E-ignition timing of cyls 2 and 3 agree with the timing of 1 and 4. Following that I guess I will pull the carbs. We'll be out of town most of the week so probably won't get them back on the bike till next weekend.
I admit there is a part of me that is thinking that since the bike runs great except for the stuttering in a rather narrow, low rpm range, why not just leave it alone? But the major part of me says, "No, I can't deal with that!"
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To check sparks for each cylinder on these, you may need to flip the induction clamp for the difference in each pair of coil leads from single coil to get signal. They are inverted in comparison to one another as exit each end of that coil, with some clamps directional and need that flip flop to get a read.
I think it's worthwhile at this point to see if you can chase it down. Easily said by me not doing the work :) as it's good to have them glitch free, which they should be capable of. Satisfying too, if you get it completely debugged and they are usually very linear in smoothness from their original design intent.
Hopefully you can get a clearer picture as you test the different elements.
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At the risk of sounding naive you mention it's a low speed stutter - is it possibly a feature of an engine that always needed revs to perform & run smoothly?
Not so much a stutter as low revs death due to a lack of low down torque - as has been said previously opening the throttle wider often makes it seem worse? I guess it might be a question of degree especially if the bike has run without the stutter previously.
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All the spark/timing tests were good. I didn't pull the carbs today...just couldn't get up the enthusiasm...maybe tomorrow.
The stutter/roughness I am speaking of occurs just above idle - 1500-1800 RPM. It is most apparent if holding a steady throttle in that range - say 1st or 2nd gear in slow-moving traffic or maneuvering in a parking lot.
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The stutter/roughness I am speaking of occurs just above idle - 1500-1800 RPM. It is most apparent if holding a steady throttle in that range - say 1st or 2nd gear in slow-moving traffic or maneuvering in a parking lot.
I have it in both my CB350 twin and CB750, I've yet to be able to tune it out. Maybe a little faster, 30mph in 4th gear is the when its most noticeable, just when you crack the throttle it doesn't like staying there. Give it a fistful and away it goes
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Pretty much the same symptoms!! I was thinking it was my #1 carb idle circuit since it doesn't respond properly to the movement of the airscrew. I'm going to try to remove/clean out that jet with the carbs still on the bike. I squirted carb cleaner through all the jets when I had everything disassembled but I didn't actually check with a wire to be sure the idle jets were totally clear - stupid on my part. But I'm only checking #1 since the other three react properly to airscrew adjustment.
Removing the carbs/ raising the needles is the next thing I will attempt.
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Carbs are off, back at the house... One of the pilot jets was partially clogged so cleaned all with my jet cleaning tool (guitar string).
One of the pilot jet's emulsion tubes is slightly bent. Not sure how it could have gotten that way...wondering if that could have any effect on fueling. Are those jets available individually or only as a carb repair kit?
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If you need a 400 emulsion tube I have a set of good used ones PM me if I can be of help.
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Carbs are off, back at the house... One of the pilot jets was partially clogged so cleaned all with my jet cleaning tool (guitar string).
One of the pilot jet's emulsion tubes is slightly bent. Not sure how it could have gotten that way...wondering if that could have any effect on fueling. Are those jets available individually or only as a carb repair kit?
Definitely....it's fundamental to how the fuel is distributed within the oxygen carrying air volume that's just been ingested from intake stroke. The better (smaller droplets and more even distribution) the fuel charge has, then the more consistently linear the burn characteristics are when the spark happens.
If the emulsion tube has restricted abilities to "atomise" the fuel into droplets that are fine enough to be optimum, then that cylinder has difficulty in completely burning each and every firing stroke.
Obviously you the rider then feel this stumble as that cylinder doesn't contribute regularly to the output, and you either have to close or open the throttle to get it away from that characteristic.
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Thanks! Just to clarify since I used the wrong term in my previous post...
The "slow jet" is apparently the correct name for the item I called a "pilot jet." The tubular portion of the slow jet with the holes in it is the bent part to which I referred. https://www.davidsilverspares.co.uk/CB400F-SUPER-SPORT-FOUR/part_3316/
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Just because DS refers to it by that name doesn't mean it's right. I've always referred to it as either the idle jet or the pilot jet. I think slow jet is more of an American term.
Emulsion tubes are the ones above the main jet, lots of really small holes in them as a rule.
I think I'm right in thinking you mean the emulsion looking type tube on the pilot jet that's bent.
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Yes. I tried to take pics of it but it's too small to be really able to see but the bent one has some holes that are not round, they are quite egg-shaped. it's as if the jet had been screwed in with something stopping the tip from moving forward so it buckled.
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What size is stamped on it Mike?
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40 and is identical to the other three...except for being bent! :)
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FWFW - In cleaning all the passages with guitar strings I think I figured out what might have happened to that pilot jet. There are two fittings on the carb that the pilot jet can screw into. One is the actual fitting for it, the other has a blanking plug. Which is which (plug or passage) is determined by whether it's a 1-2 carb or a 3-4 carb. The blanking plug is far enough in where the jet can start threading in. I suspect someone did that - started screwing it in and, when the tube 'bottomed' against the plug, probably thought that the threads were just a bit buggered and continued screwing it in. Before realizing they had installed it in the wrong fitting, the jet was distorted. Of course, I can't say for sure that that happened but it would cause exactly the damage that exists and I can't think of any other way the damage could occur.
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Sounds entirely feasible, agree that it would likely be something of this direction that could compress that section with holes in it.
I'm amazed that for a relatively mundane production item, these carburettor, that they are so finely resolved in design and production tolerance, all made some considerable time ago too.
They really are very very accurate in their manufacture and provide extremely precise metering of fuel for the correct response in running these engines. It's generally when first working on them that a recalibration is needed to just how small a fault can produce errors in their use. I doubt you'll be the last to have to go into them again in a process of getting fully sorted, that's quite usual from experiences on here ;D
They are quite a marvel really, and hopefully you'll have got to the reason why there's glitches in power delivery.
Quite worthwhile in working through them really, hopefully productive when you next run them as well.
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Do the slide needles wear as a "normal" thing to consider for replacement? Amal Concentric Carb needles on BrittBikes typically wear and need replacing periodically but I haven't seen any posts here indicating that is an issue with these carbs.
The four needles all look perfect to me under a loup - no difference in profile for any of them. one has some discoloration on the lower section but I can't feel anything with a fingernail.
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Interesting point early SU carbs had a fixed needle so they was generally no wear. Later SU carbs had a poor quality spring loaded needle so the jets in the base were worn oval - mainly caused erratic tick over issues.
The Honda carbs are well engineered like early SU's I have not seen any similar wear in my short experience on motorcycles. At high mileage due to wear in the slider sides you would eventually see wear.
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I have to admit that now, having identified issues in the pilot circuits, I'm thinking of leaving the needles in the OEM position rather than raising them a notch. It seems to me the best thing is to start out with everything "stock" first.
Interestingly, I ran across this quote in some searching on this site:
"Driving along in first gear just barely above idle, there should (actually MUST) be some blubbering, but it should clear up immediately at about 1/16 throttle." That makes it sound like what I find annoying is "normal."
That quote is from the first post here:
http://forums.sohc4.net/index.php?topic=5410
It is in item 2 under the heading, "How do I tune the carbs?":
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Today I went out on the bike for the first time since completely going through/reinstalling the carbs. All carb settings were completely stock with all original parts except the Orings. Air screw position was 2 turns out. Float level to spec and idle set at 1200RPM and choke/fast idle set per Honda shop manual.
The results: Frankly, it could not have run better! No bog at all, smooth 1200 RPM idle, and it takes throttle from any position with no hesitation/stuttering or any other bad behavior!! :)
As mentioned in earlier posts, I had been thinking about adjusting the needle position and making extreme airscrew adjustments in hopes of eliminating the bog/get the bike running as it should and then I got to thinking (usually hazardous for me but it paid off this time), "When the bike was new, did it bog while taking the throttle?" I searched and found an original Cycle World 1977 road test of the bike. Quite the contrary, they commented on how well it took the throttle going to WOT from any throttle position in any gear. As an aside, they also commented that the brakes were strong but they weren't too impressed with the suspension when pushing hard.
So based on that I figured that it SHOULD run perfectly if everything was set per spec and functioning properly. And it does!
In my case three things were "changed." As I mentioned in an earlier post, two of the pilot jets were slightly bent and had a couple of the emulsion holes restricted/egg-shaped so I replaced those with new "genuine" pilot jets (in Honda plastic bags and with the Kiehen logo on the jets). Also the float levels were at 24mm so I reset them to spec. Additionally, although I had cleaned the carbs the first time I pulled them, clearly I did not clean them well enough to ensure all passages were clear. One of the (good) original pilot jets was totally blocked. I had sprayed carb cleaner through it the first time I disassembled the carbs but this time I cleaned all passages/jets out with a guitar string.
Of course, I should have done that the first time which reminds me of an old saying, "If you don't TAKE the time to do it right, you will have to MAKE time to do it over! ;)