Intake Restrictors?
08-16-2005 | 11:45 AM
#1
Thread Starter
Member
Squid
Joined: Aug 2005
Posts: 88
From: San Diego, CA
Intake Restrictors?
Hey folks - I'm very new to the whole SuperHawk thing, the PO jetted (DynoJet - doesn't know what stage) and put a Leo single can on the bike with his own exhaust. All nicely done.
He hasn't touched the timming nor the manifold - but I'd seen in earlier google searches (which I can't find now!) that the stock rubber mounts that hold the carbs to the head have restrictor rings in them. They of course claim huge gains all across the board if you advance the timming, put in their jets, and pull out the restrictors.
Is there any truth to this? This bike feels a little less snappy and a little less powerful than the only other SuperHawk I test drove. These guys claimed improved mileage, too, for advanced timming. Personally, I'm tired of bikes eating cylenders from too much timming (or is it too much boost?) - and I bought this bike as reliable, fun transportation. But if this will get me back a bit of my mid range (which isn't lacking but could be stronger) and help mileage, that would be great.
Also, I can run 87 octane? That's what I've heard. The bike is a '98.
Thanks in advance, folks!
-Abe.
________
Strain index
He hasn't touched the timming nor the manifold - but I'd seen in earlier google searches (which I can't find now!) that the stock rubber mounts that hold the carbs to the head have restrictor rings in them. They of course claim huge gains all across the board if you advance the timming, put in their jets, and pull out the restrictors.
Is there any truth to this? This bike feels a little less snappy and a little less powerful than the only other SuperHawk I test drove. These guys claimed improved mileage, too, for advanced timming. Personally, I'm tired of bikes eating cylenders from too much timming (or is it too much boost?) - and I bought this bike as reliable, fun transportation. But if this will get me back a bit of my mid range (which isn't lacking but could be stronger) and help mileage, that would be great.
Also, I can run 87 octane? That's what I've heard. The bike is a '98.
Thanks in advance, folks!
-Abe.
________
Strain index
Last edited by AbeFM; 03-17-2011 at 12:42 PM.
08-16-2005 | 03:17 PM
#4
Thread Starter
Member
Squid
Joined: Aug 2005
Posts: 88
From: San Diego, CA
So you're saying the restrictor is new in 2000, or it went away in 2000? Looks like a pain to get to those so I'd rather not pull it apart if I don't need to.
The other bike I drove, which was much snappier, was a 2002, I think. Very similar, but perhaps that's part of it. I'm wondering if I should pull the "extra spacer washer thingie" out of the jet kit. Then again, the plugs look absolutely perfect - iridiums that have been in there for 6k miles - they look like a darned textbook - so perhaps I should just leave it.
________
WEED VAPORIZER
The other bike I drove, which was much snappier, was a 2002, I think. Very similar, but perhaps that's part of it. I'm wondering if I should pull the "extra spacer washer thingie" out of the jet kit. Then again, the plugs look absolutely perfect - iridiums that have been in there for 6k miles - they look like a darned textbook - so perhaps I should just leave it.
________
WEED VAPORIZER
Last edited by AbeFM; 03-17-2011 at 12:43 PM.
08-16-2005 | 07:02 PM
#5
Senior Member
MotoGP
Joined: Jan 2005
Posts: 3,844
From: Gainesville FLA.
Re: Intake Restrictors?
Yes you can use regular gas even 87. I own a 98 and when I did my carbs I did not see any restrictors but I don't know if they are all the same. The California models may be different and the previous owner might have taken mine out but I did not have them.
08-16-2005 | 08:31 PM
#7
Slacker
Superstock
Superstock
Joined: Jun 2005
Posts: 489
From: San Antonio, TX
Re: Intake Restrictors?
(1) the PO jetted (DynoJet - doesn't know what stage) and put a Leo single can on the bike with his own exhaust.
(2) but I'd seen in earlier google searches (which I can't find now!) that the stock rubber mounts that hold the carbs to the head have restrictor rings in them.
(3) But if this will get me back a bit of my mid range (which isn't lacking but could be stronger) and help mileage, that would be great.
(4) Also, I can run 87 octane? That's what I've heard. The bike is a '98.
-Abe.
(2) but I'd seen in earlier google searches (which I can't find now!) that the stock rubber mounts that hold the carbs to the head have restrictor rings in them.
(3) But if this will get me back a bit of my mid range (which isn't lacking but could be stronger) and help mileage, that would be great.
(4) Also, I can run 87 octane? That's what I've heard. The bike is a '98.
-Abe.
(1) & (3) From all that I've read online about single exit exhaust systems on V-twin bikes, I'd have to suggest changing your setup back to a dual muffler setup. Supposedly the single can system puts a choke-hold on the mid-range power delivery. ALSO, the midrange is VERY sensitive to needle settings as well as pilot screw adjustment. Changing the length of the intake runners can also have a noticeable effect on the mid-range.
(2) To the best of my knowledge, none of the US model superHawks have the metal restrictor rings installed, but the 2000 year models and possibly the 2001 DID have intake rubbers with slightly slightly smaller porting, possibly in an attempt to cure a stalling problem found in SOME bikes.
(4) My '98 owner's manual states that this motorcyles is designed to operate properly on any standard pump gas with an octane rating of 86 or higher
08-16-2005 | 08:41 PM
#8
Senior Member
MotoGP
Joined: Jan 2005
Posts: 3,844
From: Gainesville FLA.
Re: Intake Restrictors?
I've read that as well about the single exhaust, however I talked to a couple of dyno mech. who told me different. I've been thinking about this mod for a long time and have done a bit of research on it. I've read and have been told by the dyno guys as long as you have a good mix where they join it works fine. They both had experience doing it on the superhawk. The only thing that got me really thinking about it was that the pro racing rc51's have single exhaust and I think it just looks cleaner. I don't have any idea what your exhaust looks like or mixes but it could have something to do with it if it's not scaveging well.
08-17-2005 | 12:02 AM
#10
Thread Starter
Member
Squid
Joined: Aug 2005
Posts: 88
From: San Diego, CA
Re: Intake Restrictors?
So apparently I just found out my intake box was "swisscheesed to improve flow"...
So now I guess I'll either tape it over and see if it gets better, or remove the top alltogether as discussed in another thread.
The bike stalled today after a 5 minute run at constant speed (low revs in traffic, high gear) when slowing to a stop with the clutch in. Had to get to nuetral in a hurry (can I disable that?!) and restart. It generally idles well, but when it's cold out needs a lot more idle screw than when it's warm, and I don't like idleing at 2k+ when it's warm. Seems too nice a bike to have to "keep alive" by careful throttle managment. Any ideas?
Thanks as always!
-Abe.
________
Honda atlas cars pakistan specifications
So now I guess I'll either tape it over and see if it gets better, or remove the top alltogether as discussed in another thread.
The bike stalled today after a 5 minute run at constant speed (low revs in traffic, high gear) when slowing to a stop with the clutch in. Had to get to nuetral in a hurry (can I disable that?!) and restart. It generally idles well, but when it's cold out needs a lot more idle screw than when it's warm, and I don't like idleing at 2k+ when it's warm. Seems too nice a bike to have to "keep alive" by careful throttle managment. Any ideas?
Thanks as always!
-Abe.
________
Honda atlas cars pakistan specifications
Last edited by AbeFM; 03-17-2011 at 12:43 PM.
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