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Carb sync & rejet....approx how many shop hours?

Old 02-25-2016, 07:36 AM
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Carb sync & rejet....approx how many shop hours?

I have a 1998 SH with 30k.
Just put on Two Bros slip on exhaust (shortened cans).
The bike runs pretty rough between 1500-3000 rpm
With a lot of popping on decel.
I'm planning on talking to the local shop about the rejet & carb sync.
Just curious how many hours of labor I'm looking at?
Thanks
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Old 02-25-2016, 08:52 AM
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carb sync maybe 30 minutes
adjust tps if needed or asked for
and jets around 2 hours if it goes right first time.

tank off
airbox off
carbs off
bowls off quick clean
jets out
new jets in
carb on
airbox on
tank on backwards
sync
(if requesting tps too) airbox off, carbs off tps adjust then carbs and airbox back on
tank on

ride away

Last edited by roasty_duck; 02-25-2016 at 08:54 AM.
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Old 02-26-2016, 07:59 AM
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Smile

Originally Posted by roasty_duck View Post
carb sync maybe 30 minutes
adjust tps if needed or asked for
and jets around 2 hours if it goes right first time.

tank off
airbox off
carbs off
bowls off quick clean
jets out
new jets in
carb on
airbox on
tank on backwards
sync
(if requesting tps too) airbox off, carbs off tps adjust then carbs and airbox back on
tank on

ride away
Thanks!
Now when I talk to the mechanic....I'll sound like I know the needed procedure.
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Old 02-26-2016, 08:15 AM
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Originally Posted by 118811 View Post
Thanks!
Now when I talk to the mechanic....I'll sound like I know the needed procedure.
Just curious, have you read Hawks carb re-jet sticky thread? If not, you should.
If your mechanic is not experienced with the VTR his re-jet will likely make things worse, not better. What works and is customary on other bike engines is not what the VTR needs.
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Old 02-26-2016, 08:26 AM
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agreed with above, im still trying to undo the work the previous owner did :/

reality its taken me 9 hours so far and not sorted it
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Old 02-26-2016, 10:02 AM
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Thanks for the info, Xeris.
I'll read that����

Last edited by 118811; 02-26-2016 at 10:10 PM.
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Old 02-26-2016, 10:23 AM
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i only touched my first superhawk carb a few days ago, not i can tell you where everything is and the colour and probably writing on them
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Old 02-26-2016, 09:07 PM
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I have gotten thru about 6 page of Hawks thread on carb setup.
I know my bike needs it....but I am now hesitant.
SOOOOOO many variables & not knowing what my current setup is
I have know idea what to tell the mechanic!
But I do hate the fact that my bike sounds like a sick Harley on decel...& does buck and snort on occasion between 1500-2500.
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Old 02-27-2016, 12:52 AM
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The thing with VTR carbs and set up is that what works for one may not work for others.


It is a game of trial and error, although a base line helps.

I have had my carbs off 19 times to date and am happy with how the bike performs now.

Effort is rewarded , and patience is required.

I for one enjoy the carbs, although at times I have been frustrated with them.

When you get them right your bike will be a joy to ride.
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Old 02-27-2016, 05:15 AM
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simplest thing to do is get the carbs apart and look for yourself, see what jets are in there, check the air filter to see whats in it and if it needs cleaning or renewing.

thats an hour or so job which will save you some hassle if it solves the problem, even more so if its got silly jets in it then set it to standard and work from there.

mine had 48 pilots and 190 mains, i had so many issues with it but i set it to stock and worked from there, i may fit the 180 mains and leave oem filter in but as above it differs for everyone.
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Old 02-27-2016, 10:15 AM
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Not sure about around you but carbs are like a magical world few dare tread around here.

They are going to charge you way more than 2-3 hrs. They may wait for after or half way through the job to tell you that.

Popping on decal is not a big issue. Rough running may be. Do you know what air filter have it it? That is very important, these bikes don't like K&Ns.

If you change the mains and get them super clean, that is a good start. You are probably experiencing dirty carbs anyway so it masks the true performance of the carbs.

See what the quote you and report back. Many mechanics these days wont go near carbs, many shouldn't.
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Old 02-27-2016, 10:27 AM
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Originally Posted by smokinjoe73 View Post
Not sure about around you but carbs are like a magical world few dare tread around here.

They are going to charge you way more than 2-3 hrs. They may wait for after or half way through the job to tell you that.

Popping on decal is not a big issue. Rough running may be. Do you know what air filter have it it? That is very important, these bikes don't like K&Ns.

If you change the mains and get them super clean, that is a good start. You are probably experiencing dirty carbs anyway so it masks the true performance of the carbs.

See what the quote you and report back. Many mechanics these days wont go near carbs, many shouldn't.
This was my original thought..too!!
My bike never stalls....so I may live with it for now.
But, I will have to get in there {me or a mechanic} to see what is my current setup is.
Thanks again to all of you who responded.
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Old 02-27-2016, 11:12 AM
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Popping will be the pair system which is easy to plug.
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Old 02-27-2016, 11:47 AM
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Originally Posted by NZSpokes View Post
Popping will be the pair system which is easy to plug.
Haha, I thought the pair system, was something on Cal. Bike for emission control !!
I appreciate the heads up. :0)

Will def. do the block off when I get in there.

Last edited by 118811; 02-27-2016 at 09:08 PM.
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Old 02-27-2016, 02:06 PM
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Well......I noticed today that my choke was pulled about a .25" out.
I never have had to use that to start the bike here in Honolulu.
I pushed it in & it does seem to run better with less pop on decel, ;-)
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Old 02-28-2016, 04:28 AM
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Originally Posted by smokinjoe73 View Post
Not sure about around you but carbs are like a magical world few dare tread around here.

They are going to charge you way more than 2-3 hrs. They may wait for after or half way through the job to tell you that.

Popping on decal is not a big issue. Rough running may be. Do you know what air filter have it it? That is very important, these bikes don't like K&Ns.

If you change the mains and get them super clean, that is a good start. You are probably experiencing dirty carbs anyway so it masks the true performance of the carbs.

See what the quote you and report back. Many mechanics these days wont go near carbs, many shouldn't.
That in SPADES...well said.

Any shop telling you less then 2-3 hours is inexperienced, unrealistic, being deceptive, or likes to give work away for free.

And there are MANY parts changers out there in today's shops (always has been) which is fine if you need a part changed ,,not ok if you need a complicated assembly adjusted based on observations, experience and feedback.

IMHO, doing serious carb work without a dyno, is not the better way.. if not right there while doing the work at least an run after your set up run to confirm.
The days of "reading" plugs is gone unless you're running a race gas.
That's not to say a good tuner can not get it right by "feel" without a Dyno, just it's a lot quicker and more accurate using one.

Pull the carbs, a good sonic clean, base line the carbs with a known working set up and then go from there based on how it runs....(or go find a tuner with a dyno that knows carbs,,,and they can dial it in in a few sessions)
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Old 02-28-2016, 07:12 AM
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Funny, Erik, I was thinking that on my ride to work, that a dyno guy is the last bastion of someone who can jet on the fly with real testable results.

I still vote for the sonic cleaning to establish a baseline. You may not need anything more than that.

Plus they are cheap enough that they pay for themselves if you compare it to shop time.

Do remove the pair system. Search it on here. It will save you a ton of work in the long run.
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Old 02-28-2016, 09:08 AM
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i need to remove the pair on mine but need to find sizes of the plugs i need and images or locations on a diagram of what i plug, found a thread on here but pics are gone
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Old 02-28-2016, 09:48 AM
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Living on Oahu, here in Hawaii......is beautiful. But we have limited resources & no track to promote growth of bike tuner's
mechanic's with carb experience....or any fine tuning is rare here.

Plus I only paid $2K for this bike & plan to keep it an economical mode of fun transport.
So a lot of what has been suggested here is just not a viable option for me.

What is a "sonic" clean?
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Old 02-28-2016, 09:49 AM
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a sonic cleaner is a device that uses sonic waves and water/cleaning solution to clean crud off, theyre not expensive around 40 for a decent one in the uk.
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Old 02-28-2016, 04:59 PM
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Originally Posted by 118811 View Post
Living on Oahu, here in Hawaii......is beautiful. But we have limited resources & no track to promote growth of bike tuner's
mechanic's with carb experience....or any fine tuning is rare here.

Plus I only paid $2K for this bike & plan to keep it an economical mode of fun transport.
So a lot of what has been suggested here is just not a viable option for me.

What is a "sonic" clean?
Then you do the best you can....... though there are tuners with Dynos in Oahu..

a Sonic cleaner is a tank that uses sonic waves and a "soap" to clean... google it and be amazed.
My tank cost me $3k... you can get a small one that will fit parts of a SH carb at a time for $60 ... you will not get a SH carb assembly in that small tank... it will not work as good as a commercial professional tank, but it will work good enough.

Get and use the correct solution for aluminum carbs...This is what i use from Omega Sonic
OmegaClean Ultrasonic Cleaning Soap though I buy it in 5 gal containers, 10 gal at a time
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Old 02-28-2016, 07:46 PM
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Yeah.....a few of the shops do have dyno's.
But, that cost for this bike just isn't cost efficient.

I have a friend who I bought a Ducati M900 from.....he's a BMW tech.
He installed FCRs on the Monster & did some work on it for me.
He is quite meticulous.....I think I might be able to talk him into (bribe)
Into helping me (do it!!!)
Clean, get my carb setup to Hawks baseline setup.

I would just need to have all the parts on hand to do the job.
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Old 02-28-2016, 07:57 PM
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I contacted a local speed shop and he told me he wouldn't ultrasonic clean my carbs unless i removed all the brass parts, because the process would etch the brass and ultimately make any brass orifices (holes) bigger because of the process. I told him i appreciated his honesty...

Dyno tuning is certainly the way to go if you have the funds, but don't show up without more parts to test with (meaning different jet sizes, needle tapers, air filters, shim spacers, etc). A dyno run without an afr reading is a total waste of time in my opinion... And even if you get an afr reading from 0 rpm to redline, it won't tell you whether your bike will run better at 12:1 or 13:1, as each engine/type of engine is different... The testing part is very important. First to flatten the afr curve as much as possible, meaning to get it at say 12:1 from 0 rpm to redline, but then also to test at 13:1, then again at 11:1 to see which way makes more power for your engine... And that's just tuning at wide open throttle, then you have to tune (or estimate) for 75% throttle, 50% throttle, and 25% throttle...

I used to help write custom maps for fuel injected race quads and dirtbikes, so i have a little experience with it.

Ultimately though most people are happy with a bike that runs well and doesn't hiccups or stumbles. Most people don't know the difference between what they have and the last few hp the dyno can provide.

The last race quad i tested was one i built, it went on the dyno at about 45hp, and came off the dyno after tuning at 51.8hp.... 11% is a huge increase for a couple hours work...

James
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Old 02-29-2016, 03:46 AM
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Originally Posted by thedeatons View Post
I contacted a local speed shop and he told me he wouldn't ultrasonic clean my carbs unless i removed all the brass parts, because the process would etch the brass and ultimately make any brass orifices (holes) bigger because of the process. I told him i appreciated his honesty...
I've never heard that before , interesting.
I can find no such reference or warning, and in using sonic tanks for the last 6 years never seen it happen.. and yes, brass jets, needle jets are inspected under a magnifying glass post cleaning for damage, roundness and cleanness.

I've watched F1 and Moto GP techs put unobtainium hundred thousand dollar parts with brass, aluminum & titanium and other metals in sonic tanks with no concern or believed damage. If it were a common issue ,,,you think they would risk thier riders bike or car like that (or thier job)??

I'd have to assume your speed guy is either misinformed or is using the wrong cleaning soaps.
I have seen folks ruin carbs in thier $60 harbor freight sonic tank by using acidic solutions (vinegar) or simple green which is NOT aluminum safe for more than brief contact and then flushing after.

Originally Posted by thedeatons View Post
Dyno tuning is certainly the way to go if you have the funds, but don't show up without more parts to test with (meaning different jet sizes, needle tapers, air filters, shim spacers, etc). A dyno run without an afr reading is a total waste of time in my opinion...
Why would you run a dyno without AF metering equipment? Who does that? I agree with you, that would be a waste of time...
I never worked in a shop that did such a thing nor been to one like that. It never occurred to me that someone would buy and set up a dyno and not be able to use it.

Yes it would be BEST if you had the time and money to do a run, make on site adjustments, and make more runs.. but NO that is not the only way.

You can do a quick run up to temp and then 5 or 6 pulls in well under an hour with a good tech and a bike that is dyno ready ( seat off, bike basically warm, exhaust cans ready to accept probe, ECU wiring accessible so you can get the tach probe on, ect) with a good dyno operator and use it to confirm your settings. So in less than an hours time you will have great knowledge of where your fueling is, pilot, idle, main jet and transitions.. Go home, do some more seat of the pants jetting and when you feel you have made an improvement go spend another $100-150 on a Dyno session..

None of this is theory... until recently where I had access to a Dyno and Tech at the cost of having him and the wife over some weekend for BBq and beer.. the mix and match of jetting at home till it felt "right" and a single dyno session to check fueling is how I have done it for years.. in 4 states.

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Old 02-29-2016, 04:04 AM
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ultrasonic cleaners damage brass? seem perfectly fine on bullet casings
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Old 02-29-2016, 07:53 AM
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Really, for what its worth, my advise is to watch some utube videos on carb cleaning.

Really for all you know, once cleaned, all the problems would be gone.

First remove the pair system. Get some rubber plugs from home depot maybe. The valves on the head can be blocked with sheet metal cut to size with snips.

Some air box holes need to be plugged.

Getting that out of the way will let you remove the carbs. Just don't drop those screws into the intake opening.

open each carb one by one so you don't get confused on part location.

Or at least learn to remove them (take your time) then just hand them to the mechanic to clean. That should cut your bill in half.

Or go on a ridiers forum and find someone willing to walk you through it for a case of hawian beer or similar.

The effort you put into getting a coach will pay off huge in knowledge of how your bike works, which amplifies the enjoyment of owning and riding it.
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Old 02-29-2016, 07:40 PM
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Yeah we sonicate literally everything in my particle accelerator with multiple solvents like acetone & methanol, for metals such as copper, brass, stainless, silver (yes actual solid silver), tantalum etc and have no ill effects. Hell the silver gets a round soaking in nitric acid to remove buildup, comes out just fine.

The only issue with sonication or soakings parts would be material/solvent compatibility. Cleaning solution is not going to "etch" metal and any cleaning solution like Marquez posted above will be quite robust across general material a carb would be die cast out of or include as a jet.

Unless your guy is somehow using a terrible acid (which would also eat his sonicator equipment, think pouring gasoline into a syrofoam cup.) I'm not sure the issue, sounds like he doesn't want to do it :/ but he could have some really large glass sonicator what do i know hahahahah

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Old 02-29-2016, 08:24 PM
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Originally Posted by thedeatons View Post
I contacted a local speed shop and he told me he wouldn't ultrasonic clean my carbs unless i removed all the brass parts, because the process would etch the brass and ultimately make any brass orifices (holes) bigger because of the process. I told him i appreciated his honesty...

Dyno tuning is certainly the way to go if you have the funds, but don't show up without more parts to test with (meaning different jet sizes, needle tapers, air filters, shim spacers, etc). A dyno run without an afr reading is a total waste of time in my opinion... And even if you get an afr reading from 0 rpm to redline, it won't tell you whether your bike will run better at 12:1 or 13:1, as each engine/type of engine is different... The testing part is very important. First to flatten the afr curve as much as possible, meaning to get it at say 12:1 from 0 rpm to redline, but then also to test at 13:1, then again at 11:1 to see which way makes more power for your engine... And that's just tuning at wide open throttle, then you have to tune (or estimate) for 75% throttle, 50% throttle, and 25% throttle...

I used to help write custom maps for fuel injected race quads and dirtbikes, so i have a little experience with it.

Ultimately though most people are happy with a bike that runs well and doesn't hiccups or stumbles. Most people don't know the difference between what they have and the last few hp the dyno can provide.

The last race quad i tested was one i built, it went on the dyno at about 45hp, and came off the dyno after tuning at 51.8hp.... 11% is a huge increase for a couple hours work...

James
Any dyno tuning place that doesn't have a wideband sensor or any other means of checking the AFR is a scam in my eyes. Might as well let us do it on our own, blindly feeling it with the intrinsically inaccurate butt-dyno
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Old 03-01-2016, 02:27 AM
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When you remove the PAIR just turn the reeds over and plug the holes on the cover of the rocker covers

Saves buying block off plates, or cutting plates to fit.

My bike has been like that for approx 4 years and no probs.

Very cost effective!

Last edited by kenmoore; 03-01-2016 at 11:38 AM.
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Old 03-05-2016, 02:05 PM
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I read somewhere on here that some SH's run better with 87 octane gas.
I'm trying a tank of it right now & the first 20 miles have been I must admit better. Less backfire & jolting, bucking 2-4K range at lower speeds.

Any danger's I should be aware of?
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