Zip Ty vs. R&D Powerbowl


70 replies to this topic
  • ncmountainman

Posted December 19, 2007 - 10:29 AM

#61

i sent my carb to zipty awhile back and wanted the full monty but the bowls were out of stock so i went with just the adj lj cover. everything works much better than a stock fcr and the adj lj adds more tuneability(and yes it can be tweaked easily to conditions just by loading the motor up against a bank until the tire spins,and yes it does vary with conditions) but the bottom end performance was still lacking in the rough stuff(even after its dialed in) and i spoke to dean about the float bowl maybe fixing that... he said thats what it was designed for. so zipty agreed to swap out(for more $$ of course) because they were now in stock. i got it and the main difference is the clearances to the float are much tighter and there isn't as much crap (valleys and protrusions in the bowl cavity) i'm guessing that helps to keep the fuel more stable (less sloshing) i was kinda disappointed with the machining tolerances and there were several borderline mistakes, also a couple of design flaws such as the fuel screw won't go in when the bowls in place,and the bowl lip is much thicker so that the screws barely catch when they go through with the drain hose brackets(i had to eliminate the brackets) and the idle adjuster didn't bolt up properly either (had to mod it and mount with one screw) we'll see this wknd if the bowl really makes a difference:thumbsup:

  • andy250

Posted December 19, 2007 - 11:25 AM

#62

And what's your opinion as to whether the carb needs any more help?


I haven't been able to ride the bike since having the mod done (it's cold and wet here now). The bike does seem to run MUCH crisper on the stand though. I'll likely keep it as is for now and evaluate how it performs in the spring.

  • R1DEAN

Posted December 21, 2007 - 04:35 PM

#63

i sent my carb to zipty awhile back and wanted the full monty but the bowls were out of stock so i went with just the adj lj cover. everything works much better than a stock fcr and the adj lj adds more tuneability(and yes it can be tweaked easily to conditions just by loading the motor up against a bank until the tire spins,and yes it does vary with conditions) but the bottom end performance was still lacking in the rough stuff(even after its dialed in) and i spoke to dean about the float bowl maybe fixing that... he said thats what it was designed for. so zipty agreed to swap out(for more $$ of course) because they were now in stock. i got it and the main difference is the clearances to the float are much tighter and there isn't as much crap (valleys and protrusions in the bowl cavity) i'm guessing that helps to keep the fuel more stable (less sloshing) i was kinda disappointed with the machining tolerances and there were several borderline mistakes, also a couple of design flaws such as the fuel screw won't go in when the bowls in place,and the bowl lip is much thicker so that the screws barely catch when they go through with the drain hose brackets(i had to eliminate the brackets) and the idle adjuster didn't bolt up properly either (had to mod it and mount with one screw) we'll see this wknd if the bowl really makes a difference:thumbsup:


No mistake, all these areas are designed on purpose. The bowl thickness
is set to work with all the various length screw from each manufacturer,
the fuel screw clearance is designed to retain the screw, many of the
after market fuel screws vibrate out while riding. I usually set the fuel
screw before I install the bowl anyway, 6 of 1, half dozen of the other.

As far as machining tolerances, not sure what you are referring to,
I am as anal as the next guy, This part passes my approval, I have
a 37 year reputation on the line.

Dean@R&D

  • Wes Woodin

Posted December 21, 2007 - 06:05 PM

#64

No mistake, all these areas are designed on purpose. The bowl thickness
is set to work with all the various length screw from each manufacturer,
the fuel screw clearance is designed to retain the screw, many of the
after market fuel screws vibrate out while riding. I usually set the fuel
screw before I install the bowl anyway, 6 of 1, half dozen of the other.

As far as machining tolerances, not sure what you are referring to,
I am as anal as the next guy, This part passes my approval, I have
a 37 year reputation on the line.

Dean@R&D

I have never had a problem with my GYTR fuel screw with the stock fuel bowl. I have ordered my powerbowl and will have it any day. I can't wait to see the performance difference and also experience the convenience of being able to adjust it on the fly. I guess we will see if there will be a problem with the GYTR fuel screw. I'm confident that there will not be.:banghead:

  • grayracer513

Posted December 21, 2007 - 06:18 PM

#65

I have never had a problem with my GYTR fuel screw with the stock fuel bowl.

Some aftermarket fuel screws come with their own springs, which is a nice touch, but some of those springs are somewhat weaker than the OEM spring. That leads to those particular screws dropping out, and getting an unnecessarily bad rep. My Zip-Ty screws, two of them, had screws that appeared weak, IMO, so I simply set them aside and used the original spring. No problem. And yes, the bowl is stock.

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  • Wes Woodin

Posted December 21, 2007 - 06:26 PM

#66

Some aftermarket fuel screws come with their own springs, which is a nice touch, but some of those springs are somewhat weaker than the OEM spring. That leads to those particular screws dropping out, and getting an unnecessarily bad rep. My Zip-Ty screws, two of them, had screws that appeared weak, IMO, so I simply set them aside and used the original spring. No problem. And yes, the bowl is stock.

I spoke with steve at Zip TY and he told me that they were using stronger springs now when you get their fuel screw. I did order 2 stock screws with washers and o rings from Yami just in case. I will go to Home Deopt and size an "o" ring to go around the base of the fuel screw to add a little resistance where it goes through bowl if I have a problem. I'm curious to see the difference in these bowl as far as thickness and clearences.

  • ncmountainman

Posted December 22, 2007 - 08:16 AM

#67

No mistake, all these areas are designed on purpose. The bowl thickness
is set to work with all the various length screw from each manufacturer,
the fuel screw clearance is designed to retain the screw, many of the
after market fuel screws vibrate out while riding. I usually set the fuel
screw before I install the bowl anyway, 6 of 1, half dozen of the other.

As far as machining tolerances, not sure what you are referring to,
I am as anal as the next guy, This part passes my approval, I have
a 37 year reputation on the line.

Dean@R&D

no disrespect,but shouldn't that information be passed on to the consumer...such as put the fuel screw in before tightening the screws that may need to be longer than stock? and as far as the machining mistakes the lip that is turned into the bowl to retain the ap diaphram; the OD is offset from the ID enough to make one side paper thin and razor sharp up against the rubber diaphram,and in the ap cover there is a hole drilled just below and across parallel to the machined mating surface that is burned through from the drilling process and again paper thin. some of my extensive mechanical experience has included several yrs as a machinist in nuclear facilities where tolerances are down low as .001" or less(so i know anal) i really didn't want to get into this,and i realize alignment of a cast piece in a jig can be critical. aside from a very nice casting the machine work looks to be done with less attention to detail; to the point where i think it might be a borderline problem....i might add that it does work and i'm not sure if if these poor tolerances will become a issue later but as long as it squirts fuel i'm ok.
as far as differences in performance it seems to have a more powerfull squirt than just the R&D adjustable ap cover on the stock bowl(you can actually feel the difference in the throttle) and it wants to run leaner off the pj than before but when you do it introduces alot of popping on decel when your just barely on/off the throttle(not squirting much fuel) its made it harder to dial but i've only spent an hour on the new bowl so i'll get it eventually. it seems to have gotten rid of that pesky stutter in the rough stuff so it did what it was supposed to:thumbsup:

  • Wes Woodin

Posted December 22, 2007 - 09:30 AM

#68

no disrespect,but shouldn't that information be passed on to the consumer...such as put the fuel screw in before tightening the screws that may need to be longer than stock? and as far as the machining mistakes the lip that is turned into the bowl to retain the ap diaphram; the OD is offset from the ID enough to make one side paper thin and razor sharp up against the rubber diaphram,and in the ap cover there is a hole drilled just below and across parallel to the machined mating surface that is burned through from the drilling process and again paper thin. some of my extensive mechanical experience has included several yrs as a machinist in nuclear facilities where tolerances are down low as .001" or less(so i know anal) i really didn't want to get into this,and i realize alignment of a cast piece in a jig can be critical. aside from a very nice casting the machine work looks to be done with less attention to detail; to the point where i think it might be a borderline problem....i might add that it does work and i'm not sure if if these poor tolerances will become a issue later but as long as it squirts fuel i'm ok.
as far as differences in performance it seems to have a more powerfull squirt than just the R&D adjustable ap cover on the stock bowl(you can actually feel the difference in the throttle) and it wants to run leaner off the pj than before but when you do it introduces alot of popping on decel when your just barely on/off the throttle(not squirting much fuel) its made it harder to dial but i've only spent an hour on the new bowl so i'll get it eventually. it seems to have gotten rid of that pesky stutter in the rough stuff so it did what it was supposed to:thumbsup:

NC Mountain I'm here in NC too. Question?, I'm assuming that you are using a stock fuel screw?

  • ncmountainman

Posted December 22, 2007 - 03:09 PM

#69

NC Mountain I'm here in NC too. Question?, I'm assuming that you are using a stock fuel screw?


kouba link fuel screw,but the threads are all gonna be the same size;if i knew that it wasn't gonna fit would have been no issue... but my bull in a china closet came thru and i forced it thru without loosening the screws,kinda dinged up the threads a little:excuseme:

  • R1DEAN

Posted December 22, 2007 - 04:29 PM

#70

kouba link fuel screw,but the threads are all gonna be the same size;if i knew that it wasn't gonna fit would have been no issue... but my bull in a china closet came thru and i forced it thru without loosening the screws,kinda dinged up the threads a little:excuseme:


Mountain Man, PM me your addess, I have an all brass extended fuel screw
I will send you to replace your damaged screw, no problem glad to do it.:banghead:

Dean

  • Wes Woodin

Posted January 03, 2008 - 06:32 PM

#71

Have been running the powerbowl with a 50 pilot jet because I can't get a 52 right now. I will have to tell you that the bike runs great! I'm surprised! I definitely recommend it. I can't wait to get the 52 in there, it will be perfect then. Now I have been running this with the stock 08 pipe. What a difference.:banghead:





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