FIXED: new superhawk owner, running issue constant throttle
02-27-2016, 03:32 AM
#61
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Location: New South Wales Australia
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The carbs do not sit square to the engine when seated correctly. Looking at them from the rear they slant off to the left.
Based on everything that you have described I can't stop thinking that you have an unsealed inlet tract or vacuum leak, sure your carbs may not be perfect but your problem reminds me of what happened to my perfect running VTR when I encountered a vacuum leak.
Check your petcock diaphragm by sucking on the hoses. Search the forum for the method employed to do this. Check your fuel cap to ensure it's venting correctly.Search the forum for fuel cap problems also.
There is a wealth of knowledge on here about carbs , vac leaks and the like. Search is your friend and has got me through some niggley problems on many occasions!
Kudos to you for wanting to sort this problem, if you do you will be impressed!
Let us know what happens!
When running correctly these things rock!
Based on everything that you have described I can't stop thinking that you have an unsealed inlet tract or vacuum leak, sure your carbs may not be perfect but your problem reminds me of what happened to my perfect running VTR when I encountered a vacuum leak.
Check your petcock diaphragm by sucking on the hoses. Search the forum for the method employed to do this. Check your fuel cap to ensure it's venting correctly.Search the forum for fuel cap problems also.
There is a wealth of knowledge on here about carbs , vac leaks and the like. Search is your friend and has got me through some niggley problems on many occasions!
Kudos to you for wanting to sort this problem, if you do you will be impressed!
Let us know what happens!
When running correctly these things rock!
02-27-2016, 03:54 AM
#62
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Squid
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Join Date: Feb 2016
Posts: 60
you mentioned the petrol cap, it has a race keyless cap on it...
i may switch this for the original and see what happens.
i know theres something wrong because at 2 1/4 and 2 1/2 turns out with 48 pilots it was still sucking in so much air a pair of tights over the inlet + oem filter only just strangle it...
makes me wonder how the hell it run before with the carb boot not seated properly, this is why i thought it was too much fuel, it run fairly ok with an air leak.
it was by change that after turning the fuel down on the test ride i pulled the choke out and it got a lot better than it was.
only taken about 22 hours of working time to get this far! not done yet need to adjust fuel back to 2 1/2 and switch the cap
i may switch this for the original and see what happens.
i know theres something wrong because at 2 1/4 and 2 1/2 turns out with 48 pilots it was still sucking in so much air a pair of tights over the inlet + oem filter only just strangle it...
makes me wonder how the hell it run before with the carb boot not seated properly, this is why i thought it was too much fuel, it run fairly ok with an air leak.
it was by change that after turning the fuel down on the test ride i pulled the choke out and it got a lot better than it was.
only taken about 22 hours of working time to get this far! not done yet need to adjust fuel back to 2 1/2 and switch the cap
02-29-2016, 12:26 PM
#63
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Squid
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Join Date: Feb 2016
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And im back!
this is driving me insane!
ive had pilot screw out 3 and 3 1/4 turns.. still surging
raised both needles by 3 thin shims on both and then turned pilot back down to 2 1/2 turns and its better but still surging.
Also i think im expecting too much of the power but it feels a bit weak...
itll wheelie in 1st under power with no issues but 2nd i have to clutch in at 4000rpm and almost redline before dropping the clutch to get it to lift.
Is this right?
this is driving me insane!
ive had pilot screw out 3 and 3 1/4 turns.. still surging
raised both needles by 3 thin shims on both and then turned pilot back down to 2 1/2 turns and its better but still surging.
Also i think im expecting too much of the power but it feels a bit weak...
itll wheelie in 1st under power with no issues but 2nd i have to clutch in at 4000rpm and almost redline before dropping the clutch to get it to lift.
Is this right?
02-29-2016, 06:13 PM
#64
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SuperSport
Join Date: Aug 2009
Location: Las Vegas, NV
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You should not be going out 3-3.25 turns. That would indicate your pilot jet size is too small. Did you also try leaking it out, AKA screwing the pilot screws in?
Honestly, though, you should really be checking to see if you have a vacuum leak or other problems before driving yourself nuts with getting your jetting right. Tuning it is moot if you have a vacuum leak, because you're getting "unmetered" air.
Honestly, though, you should really be checking to see if you have a vacuum leak or other problems before driving yourself nuts with getting your jetting right. Tuning it is moot if you have a vacuum leak, because you're getting "unmetered" air.
Last edited by Just_Nick; 02-29-2016 at 06:56 PM.
03-01-2016, 07:52 PM
#65
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Something still seems goofy - in my opinion the 48 pilots are too rich - so you shouldn't be having lean issues on your pilot circuit unless your carbs still have debris in the circuits.
Make sure your choke fittings aren't broken and the choke is operating properly too.
As far as wheelies - mine will stand right up with a whack of the throttle at about 3500 rpm in 1st.
Make sure your choke fittings aren't broken and the choke is operating properly too.
As far as wheelies - mine will stand right up with a whack of the throttle at about 3500 rpm in 1st.
03-01-2016, 08:55 PM
#66
That one guy
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Still curious about the petcock. Mine gave me head aches before it completely failed. And yet he hasn't responded to my question.
Mine started with power lags and evolved to complete engine shurdown. I checked it once visually. Didn't properly check it with a light. Next thing I know I was sucking gas down the vac line and the hawk would completely shut down in the higher gears at steady rpms.
It's an easy check and one that can easily be scratched off the list or could be deadly if not checked properly.
Mine started with power lags and evolved to complete engine shurdown. I checked it once visually. Didn't properly check it with a light. Next thing I know I was sucking gas down the vac line and the hawk would completely shut down in the higher gears at steady rpms.
It's an easy check and one that can easily be scratched off the list or could be deadly if not checked properly.
03-01-2016, 09:14 PM
#68
That one guy
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Yes it is an easy rebuild. Some rebuild kits are faulty. The are aftermarket rebuild kits for the most part so they are not held to the OEM standards. Some times an easy install can be the problem.
Did he double check it by pulling a vacuum through the line to make sure it was running properly and I know it's a novice question but did he hook the vac line back into the proper port.
Only questions he can awnser hahaaaa.
Did he double check it by pulling a vacuum through the line to make sure it was running properly and I know it's a novice question but did he hook the vac line back into the proper port.
Only questions he can awnser hahaaaa.
Last edited by Meier Link; 03-01-2016 at 10:17 PM.
03-02-2016, 04:01 AM
#70
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Squid
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Join Date: Feb 2016
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ive not checked the petcock as of yet, currently have a very full tank of fuel as i had it in my head, simple fix the tights took some air flow and stopped surging so i can just raise the needle and turn pilot screw out but this didnt fix it...
ill check the petcock once ive got a bit less fuel, what exacly am i looking for in the petcock? just take it off unscrew the cover to get to the diaphragm and look for damage?
can i run it without a diaphragm and no vacuum just gravity fed?
if its damaged would this mean i can turn the fuel tap on with no vacuum connected and fuel will flow?
ill check the petcock once ive got a bit less fuel, what exacly am i looking for in the petcock? just take it off unscrew the cover to get to the diaphragm and look for damage?
can i run it without a diaphragm and no vacuum just gravity fed?
if its damaged would this mean i can turn the fuel tap on with no vacuum connected and fuel will flow?
Last edited by roasty_duck; 03-02-2016 at 04:09 AM.
03-02-2016, 04:11 AM
#71
That one guy
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Check the diaphrams for holes. It's an easy check. There should be 2 diaphrams. There should be zero holes. If there is a hole you need to buy a rebuild kit. Ebay is the cheapest place to get one.
Use a flash light and hold the diaphrams against it. The smallest pin hole can cause havok.
Use a flash light and hold the diaphrams against it. The smallest pin hole can cause havok.
Last edited by Meier Link; 03-02-2016 at 04:14 AM.
03-02-2016, 06:40 AM
#73
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If I remember right I replaced my petcock diaphragm with an OEM rebuild kit that was pretty cheap - cheap insurance to make sure the thing runs.
I maintain that this issue is likely not a jetting issue - clean carbs, close to stock jets and a stock filter should not equal surging and bucking at 4,000 rpm - something either letting in too much air (air leak) or preventing fuel flow (petcock) or possibly interrupting spark (ignition problem would undoubtedly show up at higher rpm as well).
Did you look at the float needles to make sure they are operating properly and not sticking? Seems like a slim chance that is the problem, but 15 year old rubber parts can certainly cause havoc.
I maintain that this issue is likely not a jetting issue - clean carbs, close to stock jets and a stock filter should not equal surging and bucking at 4,000 rpm - something either letting in too much air (air leak) or preventing fuel flow (petcock) or possibly interrupting spark (ignition problem would undoubtedly show up at higher rpm as well).
Did you look at the float needles to make sure they are operating properly and not sticking? Seems like a slim chance that is the problem, but 15 year old rubber parts can certainly cause havoc.
Last edited by AndyMX47; 03-02-2016 at 06:45 AM.
03-02-2016, 08:25 AM
#74
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SuperSport
Join Date: Aug 2009
Location: Las Vegas, NV
Posts: 731
I paid $15 shipped for an OEM diaphragm, there is no real reason to not do it when you're chasing issues. By the time you waste all that time trying to inspect it, you could have simply replaced it. Did you also check that your choke is not damaged?
You can also spray carb cleaner around the carbs with the bike running and see if you have a fluctuation in RPM. This would indicate that you have a vacuum leak of some sort.
You can also spray carb cleaner around the carbs with the bike running and see if you have a fluctuation in RPM. This would indicate that you have a vacuum leak of some sort.
03-02-2016, 04:03 PM
#75
Member
Squid
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Join Date: Feb 2016
Posts: 60
If I remember right I replaced my petcock diaphragm with an OEM rebuild kit that was pretty cheap - cheap insurance to make sure the thing runs.
I maintain that this issue is likely not a jetting issue - clean carbs, close to stock jets and a stock filter should not equal surging and bucking at 4,000 rpm - something either letting in too much air (air leak) or preventing fuel flow (petcock) or possibly interrupting spark (ignition problem would undoubtedly show up at higher rpm as well).
Did you look at the float needles to make sure they are operating properly and not sticking? Seems like a slim chance that is the problem, but 15 year old rubber parts can certainly cause havoc.
I maintain that this issue is likely not a jetting issue - clean carbs, close to stock jets and a stock filter should not equal surging and bucking at 4,000 rpm - something either letting in too much air (air leak) or preventing fuel flow (petcock) or possibly interrupting spark (ignition problem would undoubtedly show up at higher rpm as well).
Did you look at the float needles to make sure they are operating properly and not sticking? Seems like a slim chance that is the problem, but 15 year old rubber parts can certainly cause havoc.
i keep thinking electrical problem somewhere but everything i do leads to too much air...
but i raise needle, bigger pilot, it had 190 mains and oem filter.. and it still did it.. i just dont understand
Last edited by roasty_duck; 03-02-2016 at 04:08 PM.
03-02-2016, 04:04 PM
#76
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Squid
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Join Date: Feb 2016
Posts: 60
I paid $15 shipped for an OEM diaphragm, there is no real reason to not do it when you're chasing issues. By the time you waste all that time trying to inspect it, you could have simply replaced it. Did you also check that your choke is not damaged?
You can also spray carb cleaner around the carbs with the bike running and see if you have a fluctuation in RPM. This would indicate that you have a vacuum leak of some sort.
You can also spray carb cleaner around the carbs with the bike running and see if you have a fluctuation in RPM. This would indicate that you have a vacuum leak of some sort.
choke isnt damaged and works fine, its definately getting too much air or not enough fuel so damaged choke would just let more fuel in but pulling choke makes the problem almost dissapear
Last edited by roasty_duck; 03-04-2016 at 12:43 PM.
03-03-2016, 01:05 AM
#77
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Location: New South Wales Australia
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Mate,
It's time to go to a Dyno.
Check the AFR and jet accordingly.
Then adjust the needles and mixtures to what you think is close based on what the Dyno is telling you.
Ride the beast and then adjust by the seat of the pants.
Something is amiss here!(Understatement I know)
I admire you for persisting, sometimes it takes a step outside the box to sort things.
It's time to go to a Dyno.
Check the AFR and jet accordingly.
Then adjust the needles and mixtures to what you think is close based on what the Dyno is telling you.
Ride the beast and then adjust by the seat of the pants.
Something is amiss here!(Understatement I know)
I admire you for persisting, sometimes it takes a step outside the box to sort things.
03-03-2016, 01:13 AM
#78
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Location: New South Wales Australia
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Sorry for the diatribe!
Sitting here on a hot night thinking about your problem and it just struck me, Have you checked the timing?
Just a silly question, however it could hold the answer.
Had a similar problem with the "848" after I changed the cam belts. 1 tooth out on the exhaust on the rear cylinder!
Just a thought mate!
Sitting here on a hot night thinking about your problem and it just struck me, Have you checked the timing?
Just a silly question, however it could hold the answer.
Had a similar problem with the "848" after I changed the cam belts. 1 tooth out on the exhaust on the rear cylinder!
Just a thought mate!
03-03-2016, 01:43 PM
#79
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Squid
Join Date: Feb 2015
Location: Seattle, Wa., U.S.A.
Posts: 45
My SH surges, splutters, and generally runs like sh*t between 3K-4K rpm if I run 92 octane fuel. It's still there but not as bad at higher rpms. A switch to 87 octane (ethanol-free when possible) cleans up the problem entirely and she's smooth running anywhere on the tach. Huge difference.
Not sure if this is strictly a fuel octane issue, or some other issue (TPS, jetting, other ?) that is somehow awakened by the higher octane fuel. I'm all for simple fixes so I haven't dug further into it, I just run the 87 stuff and enjoy the ride.
I realize you are way deeper into this than simply experimenting with fuel octane ,and I'm not trying to oversimplify or contradict any other advice here, just throwing it out there because I know I can basically replicate a similar running issue on my SH simply by grabbing the 92 octane fuel hose at fill-up time.
Not sure if this is strictly a fuel octane issue, or some other issue (TPS, jetting, other ?) that is somehow awakened by the higher octane fuel. I'm all for simple fixes so I haven't dug further into it, I just run the 87 stuff and enjoy the ride.
I realize you are way deeper into this than simply experimenting with fuel octane ,and I'm not trying to oversimplify or contradict any other advice here, just throwing it out there because I know I can basically replicate a similar running issue on my SH simply by grabbing the 92 octane fuel hose at fill-up time.
Last edited by Bustin; 03-03-2016 at 02:12 PM. Reason: typos
03-03-2016, 10:44 PM
#81
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SuperSport
Join Date: Aug 2009
Location: Las Vegas, NV
Posts: 731
A dyno with an AFR would be a great tool, since he'd know exactly what the air:fuel mixture is doing at specific RPM and when it's surging. From there he'd know whether to lean or enrich the mixture.
03-05-2016, 10:02 AM
#84
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Squid
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Join Date: Feb 2016
Posts: 60
Ok so, fuel tap off diaphragm looks new, bolts look new, looks like it may have been changed recently, not a single hole or any damage to the diaphragm.
so next from here is the coils...
plug caps reading infinite ohms on one and 1.99ohm on other
where can i get new caps? i tried cleaning but cant get them to 5k
so next from here is the coils...
plug caps reading infinite ohms on one and 1.99ohm on other
where can i get new caps? i tried cleaning but cant get them to 5k
Last edited by roasty_duck; 03-05-2016 at 11:08 AM.
03-06-2016, 02:43 AM
#89
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Any thoughts I had about what is wrong with this bike if it had to do with the carbs has just gone out the door when I read about the fuel you use!
Here down under I have a choice at the bowser of 94 ethanol, 91 standard unleaded, 95 unleaded and 98 unleaded all without ethanol!
My bike runs on 95 most of the time and an occasional dose of 98 with no appreciable difference in performance, or at least the bum dyno doesn't register if there is! Based on the fact that I have access to different fuel none of my carb settings are relevant, so disregard what I have previously said.
I am now starting to wonder if the previous owner was chasing this gremlin and gave up and sold the bike, especially as you say the fuel tap diaphragm is in perfect order and appears to be new.
Good luck with your endeavours.
Like I said before , check the timing, a tooth out could be the cause
Here down under I have a choice at the bowser of 94 ethanol, 91 standard unleaded, 95 unleaded and 98 unleaded all without ethanol!
My bike runs on 95 most of the time and an occasional dose of 98 with no appreciable difference in performance, or at least the bum dyno doesn't register if there is! Based on the fact that I have access to different fuel none of my carb settings are relevant, so disregard what I have previously said.
I am now starting to wonder if the previous owner was chasing this gremlin and gave up and sold the bike, especially as you say the fuel tap diaphragm is in perfect order and appears to be new.
Good luck with your endeavours.
Like I said before , check the timing, a tooth out could be the cause
03-06-2016, 06:38 AM
#90
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Post a want ad about stick coils. You can use cbr600rr models, but you need to get the wiring harness with them, then splice (solder) the superhawk harness and the cbr harness together.
If you're not comfortable doing that you may be able to have someone on here do it for you.
James
If you're not comfortable doing that you may be able to have someone on here do it for you.
James
