Just put my bike back together last night.
First, here is the definite info on the jets:
The pilot is a N224.103 type
The mains (both) are N102.221
I have a V&H SS Full Exhaust, stock intake box w/OEM filter, stock timing.
I used a #20 pilot (part # 004.564 from Sudco), #62.5 mid-main (004-270), and 132.5 main (004.298). I also got a 137.5 (004.300) that I may try later. The mains were $3 each and the pilots were #4.75 each.
Four out of the eight bowl screws rounded off when I tried to remove them (yes, used the proper bit). I got one off with an impact driver, but I had to drill the other three out. If you have to do this, drill the screw a little with a smaller bit to start a good pilot hole, then use a bit that is just one size larger than the screw thread.... then the screw head will just pop right off when you get through it. The remaining thread shaft will unscrew by hand when you get the bowl removed.
I replaced all of the screws with allen head cap screws from my local hardware store. They are metric, M4x10 by 1/2" long. I would recommend doing this. I think, with the allen head screws, I will be able to remove the bowls without taking the bike apart.
If you plan on replacing the screws, I would suggest just drilling the screws out. I think beating on the carb assembly with an impact driver isn't a great idea.
The bike runs much better when cold and just takes a minute or so to shake off any signs of cold naturedness. It was taking several miles, and it felt like it was starting out in 3rd gear until the bike got warmed up. All of that is gone now... runs great. Can't tell much difference (if any) in the mid-range. Top-end feels pretty good. Overall, it is much smoother. I'm happy with it.
I couldn't figure out how to get the needles out to shim them with the #4 washer. I had pics from a how-to, but it was for an older bike and apparently the 2001+ needle assembly is different. I didn't want to force anything and break it, so I waited.
What does the needle-shimming do? Do I need to do this? How do I get the needles out of the slide assembly?
Also, forgot to mention I drilled out the brass plugs on the mix screws and set them at 2.5 turns. What exactly do these screws affect? Shoudl I go three turns?
Anyone know what rpm ranges the various (three) jets affect?
Anyone think I should try the 137.5? I'm thinking of ordering a drop in replacement from K&N or something similar. Are the pods really loud?
Thanks. I'll post some pics I took tonight.
sweet..
My mods are going to be done by the time mid november comes.
Thanks for the part numbers, now i can get those. I am going to get the K&N clamp on from usdiesel and then rejet with my stock pipe.. with 137.5's..
i think part of my vibration issue might be that im running lean. Yesterday around 1000 feet and higher the bike actually ran with lesser vibrations than on ground level.
atmospheric pressure (volume of air) doesnt really change until about 5k feet, then it gets thinner so you should run even leaner at altitude (crest goes up to 7500ft, btw).
Quote from: pantabloatmospheric pressure (volume of air) doesnt really change until about 5k feet, then it gets thinner so you should run even leaner at altitude (crest goes up to 7500ft, btw).
Huh?
I thought
lean meant "more than the ideal amount of air in the air/fuel mix". With a thinner atmosphere I would expect the amount of air in the mix would go down....
Can somebody clear this up?
sorry, I'm sick and sleep deprived.
kerry's right, I'm wrong. Less air at altitude would make the bike run richer then...But still, at 1,000ft there is no noticable difference. In fact, manjul has ridden malibu canyons often and they climb to 2,500ft above sea level. he also rides often at the crest, 7,500ft asl...should have noticed a difference if there was one on one of these rides.
just a suggestion:
instead of drilling and extracting the fuel bowl screws, use needle nose visegrips. faster, easier, and possibly cheaper if you don't have a drill, drill bit, and extractor set!
i will admit some of the malibu canyon rides it actaully did run better .. and so did some of the ACH rides. However I dont think I did an ACH after paul adjusted teh "mixture screws".. i only did ortega. or is my memory failing.
Anyway i will be heading to napa and other places this weekend i will monitor it.
Quote from: FD3S
Anyone know what rpm ranges the various (three) jets affect?
Here's a link from
Factory Pro that has very good tuning parameters for carbs and should explain it all.
//www.factorypro.com/tech/carbtun.html
Ok, after reading the Factory Pro tuning link (thanks!), it looks like shimming my needles would help the mid-range.
So, anyone have any tips on how to do that on a 2001+? They don't seem to come apart like the older ones and I don't want to break any of that fragile looking plastic stuff in there.
Thanks
Quote from: tmc008just a suggestion:
instead of drilling and extracting the fuel bowl screws, use needle nose visegrips. faster, easier, and possibly cheaper if you don't have a drill, drill bit, and extractor set!
Actually they're brass plugs so drilling them out is required. They cover the actual screws.
ACTUALLY, i've tried it and it worked great. it has also worked for others:
http://gstwins.com/forum/viewtopic.php?t=4827&highlight=
but if you care to always be right, then do it the hard way, if you must.
(and he's not talking about the plugs that cover the mixture screws) :thumb:
ACTUALLY...
see my post above (sick and sleep deprived...and still working). I'll shut up now.
I tried the needle nose vice-grip trick... wouldn't budge 'em.
After trying an extractor that broke off in the screw and the locking needle nose plyers, I cut a slot with a dremel so I could use a large flat blade screw driver. It finally came loose. There always seems to one screw that won't budge. Did use an impact driver on one, just support the back of the screw so nothing can get damaged. Replaced them all with allen screws.
to be perfectly honest, i used regular visegrips, not the needle nose. and it takes a small bit of finese to do it right. you might want to try another's suggestion. :cheers:
Quote from: FD3SOk, after reading the Factory Pro tuning link (thanks!), it looks like shimming my needles would help the mid-range.
So, anyone have any tips on how to do that on a 2001+? They don't seem to come apart like the older ones and I don't want to break any of that fragile looking plastic stuff in there.
Thanks
The needles are underneath a pull out plastic plug you access from the top of the diaphram - just like the previous years. Take off the top of the carb,- make sure you keep track of the little "o" ring - the bike will not run correctly if you don't get it back where it belongs, remove the spring and use a needle nose pliers togently twust and lift the plastic plug that you will see there -
What purpose does that little o-ring serve?
Quote from: TurbowaffleWhat purpose does that little o-ring serve?
It seals the vacuum port to the carb body.
Here is a link to those pics I took. Nothing real earth shattering: some pics of the allen head screws and the jets. Mains are typical, but the pic of the pilot might help someone pick them out of a parts bin.
http://rx7.voodoobox.net/images/jets/
Hey MJM, thanks for the reply on the needles. I was afraid to just start yanking on things until I knew for sure that was the way they came out.
Quote from: FD3SHere is a link to those pics I took.
http://rx7.voodoobox.net/images/jets/
And thanks for the pictures.
OS
QuoteFirst, here is the definite info on the jets:
The pilot is a N224.103 type
The mains (both) are N102.221
I have a V&H SS Full Exhaust, stock intake box w/OEM filter, stock timing.
I used a #20 pilot (part # 004.564 from Sudco), #62.5 mid-main (004-270), and 132.5 main (004.298). I also got a 137.5 (004.300) that I may try later. The mains were $3 each and the pilots were #4.75 each.
I've got a stock intake and stock exhaust on my 2001. How would that change which jets I would want to choose?
i will place order for the jets today.
I got my K&N filter, my Jardine Exhaust (courtesy of Linh) is on its way - should be here tommorow.
I just need to get the jets and then do teh actual rejetting on it.
Resurrecting this thread instead of posting a new question. I will be rejetting for a lunchbox and stock exhaust on my 2001. From the matrix on the wiki, there are two people using a K&N filter and stock exhaust (come on, there must be more of you):
K&N(s) 20/62.5/137
K&N(p) 20/??/142.5
stock setup is 17.5/60/127.5, right?
I was just thinking about this from a math standpoint (I read somewhere that Mikuni jets are rated by fuel delivery rate and not diameter):
17.5 to 20 is 14% more fuel
60 to 62.5 is 4% more fuel
127.5 to 140 is 10% more fuel
Do those numbers make sense or mean anything? I'm just curious... wondering if there's a reason the change is not linear.
Anywho, I think I'll go with 20/62.5/140 and see how it works, unless someone has anything to add that hasn't been included in the wiki jetting matrix. Anyone stop me before I hit the "Order" button? Or suggest any extras I should buy should things require it. (I thought maybe a 65/67.5 mid, or 142.5/145 pilot which I seem to recall worked for some folks.)
I'm too lazy to change the exhaust (and I like the quiet), so I'm only trying to ease out some of the cold-blooded-ness.
While I'm blabbing, here's a guy that says actual flow rates compared to their ratings are really sloppy:
http://rd500lc.free.fr/technics/jet_size_en.htm
Umm... discuss?
Are the 04-06 carbs different? I know the factory jetting was a bit different, but I think the carbs are otherwise the same.
I ran 22.5/65/137.5 with my Lunchbox and stock exhaust. Honestly...I think it was on the lean side.
The lunchbox increases airflow a large amount. You're going to want to bump the fuel more than just one step on all of the circuits.
I was also running 3 turns out on the mixture screws.
If you run the jets you were thinking about running with the lunchbox, you will make the bike run even worse in the cold. It will be way lean.
Best of luck,
-Turd.
Good data point. Was it lean all over, or just in a certain range?
I don't know about 01/04 differences.
C4
I'm going to get Alpha to chime in here, he had the same jetting as me with just a Lunchbox and he had it dyno-tuned. I think he'll have better insight than me on this issue...
-Turd.
When I had my bike dynoed, I was running 22.5/62.5/135, I belive, and it was too lean for my tastes. I bumped it up to 22.5/65/137.5 and it is still just a tad lean, but not too bad. I think I could bump it up to a 140 and be perfectly happy, but I have not noticed any surging or bogging down on the upper end, and it pulls quite strongly (for a 500).
I don't have a scanner, so I'll take a picture of my dyno run and post it up here some time. It was lean all over, but only by a point or so. I figured the changes I made to my jetting were enough to correct the lean conditions, but another size up on the main jet won't hurt it I think.
The '01 and '04 carbs are pretty much the same, I believe. The '04 just added the TPS (Throttle Position Sensor) and a few other minor changes, I believe. However, they are pretty much exactly alike. The TPS was simply for emissions reasons, no doubt.
Quote from: Wrecent_Wryder on October 27, 2006, 04:34:44 PM
Couldn't be more pleased with the running performance, though it takes a little more choke than I thought it would below 50 F. I might have gotten the same using a 145 main, but it's done so well I've been hesitant to touch it.
The necessity of choke is dictated by the pilot screw and air fuel screw. The main jet has no influence over that, as it comes into operation at roughly 7000RPM.
05' GS500F
Stock exhaust
K&N stock type filter
20 pilot
65 mid
137 main
3 mm washers
3 turns on mixture
I'm at sea level and find this set up work's great for me. :cheers:
[87
Hmm.. maybe I'll try 22.5/65/140 then?
[7
I'm shooting for lunchbox and stock exhaust. I'm just looking for a selection of jets to start with, and if I'm not happy I'll buy more. Given where I'm at now, I have to get the thing to not run like poop in a stock setup. (It's a 2001 engine that's been sitting for 3 years.) I took the carbs apart and did a really crappy cleanup and got the thing running.
I'll probably buy 20, 22.5, 62.5, 65, 135, 137.5 and 140 or something like that and go with what works.
7j7