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09-03-2007, 11:06 AM Babaganoush Joined on 03-23-2007 SouthCentral Pennsylvania Posts 960 TK CARB MOD REPORT Attachment: IMG_0341.JPG This is a 'phase one' progress/performance report on my mods to the Teikei carb on my 07 bike. First of all, kudos and a thousand thanks goes to Rick (dxnomad) for sending me a set of needle washers he made to my specs. They are 9 spacers of increasing thickness that fit between the nylon spacer and the clip on the needle. Each one fits up inside the plastic cap at the top of the needle without binding. You 'Da Man', Rick. You need to get in touch with Rick if you want a set of these. I am sure any price he is asking would be worth it since I could not find anything to fit anywhere (not even Radio Shack washers). I am trying to present this in a way that can be replicated easily by someone who wants a power boost from stock. OK, so we start with a stock TK carb with nothing changed but the main jet and the needle spacing. A stock exhaust, and a modded air box http://tw200forum.com/forums/18109/ShowPost.aspx . The air box mod may or may not be necessary. Leave this for last. I put in a SMALL Mikuni 127.5 jet which are available everywhere (I got mine from my dealer for $4.00). My stock jet was a TK 126. I used Rick's spacer marked .05 to raise the needle a bit. The idle screw is now 3 1/4 turns out (can be adjusted 1/4 turn either way to see what feels best). The bike now has one heck of a lot more pull through the gears and does not exhibit any strange behavior. I have to keep a closer eye on the speedometer now since I am up to 60 in no time ( not good in a 40 or 45mph speed limit zone). I am running a 52 tooth rear sprocket and a NGK Iridium plug to round out the info. If you set everything up in the carb you can see if you need to mod the air box or not by leaving the cover off and cutting 3 pieces of hanger wire to hold the foam filter in place while you do a comparison test. A good test is wide open top speed but an even better test for me is wide open in 3rd or 4th gear. The engine is going to be in the middle of 10 grand RPMs at wide open throttle. If it stutters and stumbles at that point, you need to make some adjustments. I had to turn in the idle screw from 3 3/4 to 3 1/4 to get it to run right wide open in 4th. I still may need to back it down to 3 turns after some more testing. It should just hold that speed and run without any hiccups if you have it right. The richer mixture also make the engine run a lot cooler. No more 400 degree + temps at the plug. My max temp yesterday was 353 degrees with the air temps in the mid sixties and I was riding it like I stole it. I expect to be trying out a lot of other stuff later on but this is a good place to be for now. I feel like I am riding a 225 or maybe a 250 but then again I weigh less than 140lbs so that might have something to do with the bikes performance also. So good luck modding and "TW Power to the People".  Dave     "LOUD VALVES SAVE LIVES" -back side of Royal Enfield T-shirt    Report

09-03-2007, 6:31 PM badfish Joined on 03-14-2007 florida Posts 308 Re: TK CARB MOD REPORT where can i get a set of those spacers? i would love to get some. "if you aren't living life on the edge, then you are taking up too much space!"    Report

09-03-2007, 6:42 PM Babaganoush Joined on 03-23-2007 SouthCentral Pennsylvania Posts 960 Re: TK CARB MOD REPORT Hi badfish, Shoot a PM to Rick (dxnomad). He is the one who punched them up for me. I have no control over them. I would think a generous donation would cover his time and postage, but I can't speak for him. All I know is they are invaluable for setting up the TK carb along with new jets (which can be gotten easily). EDIT: Rick does not have a supply of these. Best bet is to order from Mcmaster-Carr mentioned later in the thread. See post by monkeystone 69. Dave "LOUD VALVES SAVE LIVES" -back side of Royal Enfield T-shirt    Report

09-04-2007, 6:55 PM mrgizmow Joined on 10-21-2006 Paradise, Calif. Posts 2,216 Re: TK CARB MOD REPORT Thanks Dave: Another post that is easy to understand, has some step by step instructions and as many previous, suggests positive results. I am real happy with the way my bike runs, but who blaks at easy hp? Now poor Rick will be overwhelmed with spacer requests. Take care....... Gerry Be safe my Friend.    Report

09-05-2007, 5:50 AM Fourcycle Joined on 08-01-2007 SE Michigan Posts 1,179 Re: TK CARB MOD REPORT It thought the idle circuit was out of the picture by the time you got to WOT on a properly set up carb.  Not so? If your only tool is a hammer everything looks like a nail.    Report

09-05-2007, 6:05 AM JoMomSophat Joined on 07-12-2006 Seattle WA Posts 803 Re: TK CARB MOD REPORT the idle circuit has little affect at wot just like the main jet shouldn't affect cold weather starting, despite what some people might tell you. the idle circuit does however deliver fuel at wot while the main doesn't deliver fuel at idle, so it does make some difference. you wouldn't be able to notice though ,it just doesn't make that much difference. GO_SEAHAWKS!!!    Report

09-05-2007, 2:45 PM Babaganoush Joined on 03-23-2007 SouthCentral Pennsylvania Posts 960 Re: TK CARB MOD REPORT Let me detail some testing I did to answer the idle circuit question. I took the bike out and it ran fine except when I was WOT in 4th. It stuttered and was not acting right. I put tape over the air box holes and it got worse. My choices then were drill more air box holes, put a thinner spacer on the needle to lean out the main jet mixture, or turn in the idle mixture screw from 3 3/4 turns. I chose the quickest way and turn the screw in 1/2 turn to 3 1/4 turns out. Did the same test and the stuttering was gone. I am not saying this is the perfect tune but it is good enough for me to leave it alone a bit. I may still take it down to 3 or 2 3/4.  Draw your own conclusions. Dave "LOUD VALVES SAVE LIVES" -back side of Royal Enfield T-shirt    Report

09-06-2007, 6:28 PM Babaganoush Joined on 03-23-2007 SouthCentral Pennsylvania Posts 960 Re: TK CARB MOD REPORT I came across some really interesting carb tuning stuff in my travels. Here it is: http://www.enfieldmotorcycles.com/forum/index.php/topic,190.0.html  and  http://www.factorypro.com/tech_tuning_procedures/tuning_carbtune,CV,high_rpm_engines.html . I will defer to the Factory Pros because that is what they do for a living-setting up racing bikes. I will be studying this to see if I need to make any changes (most likely yes).  Check out figure 7&8 here:  http://www.iwt.com.au/mikunicarb.htm Dave "LOUD VALVES SAVE LIVES" -back side of Royal Enfield T-shirt    Report

09-15-2007, 7:52 PM beaner Joined on 08-11-2007 Central Montana Posts 16 Re: TK CARB MOD REPORT Dave, thanks for the report.  I took the carb off my '07 today and removed the idle mixture plug and shimmed the needle with an .018" washer.  The bike ran a little better in the midrange after this.  Then I experimented with the idle mixture screw and settled on 2 turns out, as the bike got lazy off the bottom with more fuel. I was wondering what altitude you live and ride in.  I'm at 3000 ft. and the plug color and top end performance seem ok, but I'm interested in the thickness of the spacer you used on the needle. Do you know the thickness of the .05 spacer you mentioned? thanks, gerry    Report

09-16-2007, 12:25 AM Babaganoush Joined on 03-23-2007 SouthCentral Pennsylvania Posts 960 Re: TK CARB MOD REPORT Hi beaner, I am about sea level- 600ft or so. The thickness of the spacer is .05"  Yesterday I had the carb off and put in a larger jet. I went from a small mikuni 127.5 to small mikuni 130, left the needle spacer at .05", and turned the idle mixture screw to stock position at 2 1/4 turns out. I did not want to return the needle spacing to stock since I found that the bike will run like crap with just a bigger jet change and no needle change. I am just trying to get WOT (wide open throttle) to run strong. The idle and mid-range were good already. Right now, it seems like a see-saw to me with the idle screw on one end, the main jet on the other, and the needle spacer in the middle. The larger I make the main jet the more turns in I have to make the idle screw. With a stock jet I was able to run 3 turns out or better. The larger the jet I put in the more I have to turn the idle screw in to compensate. The bike started, idled, and revved 'normal' and strong after these changes. Very encouraging- can't wait to take it out this afternoon. I had checked the float valve spacing and it was 10mm like the manual says (10 to 11mm) so I left it alone. As far as needle spacing goes, I think I am at the top of my range at .05 inches. I had a couple of washers in before that added up to .06 or better and the bike ran like crap. So the needle spacing range may be 0 to .05 max. At altitude you may need to be leaning out the mixture instead of enrichening it. You need to take a peek at the jet markings for your main jet and if it is round or hex shaped. If you have the same TK CV carb I do the jet size may be 126 (mine), 125 or smaller. You say you are happy with WOT performance so jet changing may not have to be done. Let us know what you come up with that works at your altitude. Dave   "LOUD VALVES SAVE LIVES" -back side of Royal Enfield T-shirt    Report

09-16-2007, 5:26 PM beaner Joined on 08-11-2007 Central Montana Posts 16 Re: TK CARB MOD REPORT     Hi Dave, thanks for the prompt reply.  I think my next step will be to increase the needle spacer to about .030 total thickness.  I hope to get to that within a couple days.  I'll post results here.                      Report

09-16-2007, 5:36 PM Babaganoush Joined on 03-23-2007 SouthCentral Pennsylvania Posts 960 Re: TK CARB MOD REPORT You're welcome, beaner. I rode with the 130 in today and it is great until I hit 10k RPMs then it starts coughing. I turned in the idle screw a half turn- helped a bit but not quite right. Seems I need a jet half way between 127.5 and 130. Funny, but the plug looks great-not rich at all. I may lower the needle a bit to see if that helps. Will be trying other ways to skin a cat- later.  Dave   "LOUD VALVES SAVE LIVES" -back side of Royal Enfield T-shirt    Report

09-17-2007, 12:50 AM JoMomSophat Joined on 07-12-2006 Seattle WA Posts 803 Re: TK CARB MOD REPORT Attachment: 10000rpm.jpg you shouldn't be runnung the tw past 9000 rpm the cams just wont take that kinf of rev and your hp curve will dive and give you less HP your bike will rev down to 9000 than hp will be sufficiant to bump up into the hp black hole again where the bike stalls and you sputter back to 9000. if you want to go faster you will need to change sprockets GO_SEAHAWKS!!!    Report

09-17-2007, 6:51 PM beaner Joined on 08-11-2007 Central Montana Posts 16 Re: TK CARB MOD REPORT     Hi Dave, I added more thickness to the needle spacer.  I had to go with .036" since the only spacers I had were .018".  The bike runs good, but it was only 68 degrees F this evening when I tested it.  I have a feeling that when the temp is over 90 I might have a rich condition as it feels a little less crisp on the top end.  For the record, my bike is geared 14/45, has stock main jet, idle mixture 1 turn out (as it came from yamaha), I'm at 3200' elevation.     Thanks for your help, having your experiences as a baseline saved me some labor. gerry    Report

09-17-2007, 7:50 PM Babaganoush Joined on 03-23-2007 SouthCentral Pennsylvania Posts 960 Re: TK CARB MOD REPORT Hi JoMom, You are correct. The bike pulls best from 7k to 9k RPMs. I am only winding it out to test the carb settings. I would not ordinarily try to run or get any HP over 9k. Dave "LOUD VALVES SAVE LIVES" -back side of Royal Enfield T-shirt    Report

09-17-2007, 8:14 PM Babaganoush Joined on 03-23-2007 SouthCentral Pennsylvania Posts 960 Re: TK CARB MOD REPORT You're welcome, gerry. Glad it is working out for you. Dave "LOUD VALVES SAVE LIVES" -back side of Royal Enfield T-shirt    Report

09-19-2007, 10:26 AM bronc3 Joined on 10-04-2006 Zero Gulch, Floriduh Posts 904 Re: TK CARB MOD REPORT Do you know if the Mikuni pilot jets are of the same design as the ones in the TK? If so you could eliminate the need to have the pilot screw backed out so many turns. Meanwhile, back on the tuna boat...... '07 TW200 '03 Busa '03 Savage '06 DRZ400 '75 DT175 '08 TTR230 (SWMBO) '05 DRZ125L (shared with SWMBO) '07 YZ 250 '05 Cag '10 CBR1000 (coming soon) '04 CRF50 (the boy's) '01 PW50 (the girl's)    Report

09-19-2007, 5:03 PM Babaganoush Joined on 03-23-2007 SouthCentral Pennsylvania Posts 960 Re: TK CARB MOD REPORT I have some good news to report. I can keep the mikuni 130 jet in because I found I could regulate the mixture with the needle spacing and the idle screw. Let me explain. The last time I had the carb off I noticed that the needle never really came fully out of the main jet hole. So it has to be affecting the mixture even at wide open throttle. Today I noted that there is a constant taper in the needle in the last 3/4" at the tip. I reasoned that I could lean out the mixture at WOT if I dropped the needle a bit. I installed a .04" washer to replace the .05" that I had on. I then opened up the idle screw from 1 3/4 turns to the stock setting of 2 1/4 turns. I took the bike out for a quick spin and noted that the spitting and bad manners at WOT were gone. the bike starts and idles normally and still has great pull when running up through the gears. I might do some fine tuning by lowering the needle by another .005" to a .035" spacer and can open up the idle screw as needed. Seems to me like the main jet changes the mixture in large steps, the needle spacing works in smaller increments in between the steps, and the idle screw can fine tune in between the needle spacing. Just my shade tree mechanic 'seat of the pants' findings. Hope this can help someone trying to dial in his TK.  Dave "LOUD VALVES SAVE LIVES" -back side of Royal Enfield T-shirt    Report

09-19-2007, 5:12 PM Babaganoush Joined on 03-23-2007 SouthCentral Pennsylvania Posts 960 Re: TK CARB MOD REPORT Hi bronc, I am not sure what you mean by the same design. I know that they work in the TK carb but the numbers don't match. Based on some other posts, I think the Mikuni jets are larger. For example, a 130 mikuni might be the equivalent of a TK 132. I just wish I had bought a few sets of Torque Wiz jets before he went belly-up, then I would be dealing only with TK jets with no number jumps. Oh well, coulda-woulda-shoulda. Too late now. Dave "LOUD VALVES SAVE LIVES" -back side of Royal Enfield T-shirt    Report

09-19-2007, 9:06 PM beaner Joined on 08-11-2007 Central Montana Posts 16 Re: TK CARB MOD REPORT Quote :  Hope this can help someone trying to dial in his TK. Thanks once again, Dave.  The info you posted is most useful, as my bike with the aforementioned carb adjustments is pretty lazy getting up to top speed (but no sputtering).  I will follow your lead and decrease my needle spacing.      Happy Trails, gerry    Report

09-20-2007, 11:28 AM bronc3 Joined on 10-04-2006 Zero Gulch, Floriduh Posts 904 Re: TK CARB MOD REPORT  Babaganoush wrote: Hi bronc, I am not sure what you mean by the same design. I know that they work in the TK carb but the numbers don't match. Based on some other posts, I think the Mikuni jets are larger. For example, a 130 mikuni might be the equivalent of a TK 132. I just wish I had bought a few sets of Torque Wiz jets before he went belly-up, then I would be dealing only with TK jets with no number jumps. Oh well, coulda-woulda-shoulda. Too late now. Dave   The TK appears to be a close copy of the Mikuni carb so I was wondering if the pilot jets were of the same design as the mains are. I understand that the sizes don't always correspond to the number on the jet itself. Meanwhile, back on the tuna boat...... '07 TW200 '03 Busa '03 Savage '06 DRZ400 '75 DT175 '08 TTR230 (SWMBO) '05 DRZ125L (shared with SWMBO) '07 YZ 250 '05 Cag '10 CBR1000 (coming soon) '04 CRF50 (the boy's) '01 PW50 (the girl's)    Report

09-20-2007, 2:20 PM Babaganoush Joined on 03-23-2007 SouthCentral Pennsylvania Posts 960 Re: TK CARB MOD REPORT Hi bronc, I honestly don't know anything about the pilot jets. I seem to be able to to get all the adjustment range I need without having to change out the pilot jet. I have found at least one web site that supplies a kit for different carb/bike combinations but I seriously doubt they would have anything for the TW: http://www.dynojet.com/jetkits/motorcycle/yamaha.aspx . Maybe begging would work.  Or if you are God Almighty, you could command it. Interesting: Check out the Wide Band Commander. 500 bucks for tuning perfection.  http://www.widebandcommander.com/productinfo.htm Dave   "LOUD VALVES SAVE LIVES" -back side of Royal Enfield T-shirt    Report

09-21-2007, 10:07 PM BumbleBee Joined on 08-25-2006 Seattle Posts 47 Re: TK CARB MOD REPORT  Babaganoush wrote: Hi JoMom, You are correct. The bike pulls best from 7k to 9k RPMs. I am only winding it out to test the carb settings. I would not ordinarily try to run or get any HP over 9k. Dave Forgive me if I am misunderstanding what you are saying.  As a very amature "shade-tree mechanic" It is my understanding of carb tuning that the RPMs aren't very relevent, it's the throttle position that matters. i.e., I can be at 10k at 1/2-throttle going down hill, but that doesn't say anything about the WOT jetting.  So, jetting is for throttle position, not RPMs.  Also, plug chops need to be taken immediately, at that throttle setting (pull the clutch, kill the engine, coast over to the side of the road and pull-out the plug) sounds like a real PITA to me.  Fortunately, the bike I recently had to dial in had lots of good jetting matrix data posted online, that got me very close w/o lots of trial and error.  Apparently, it is a common error to ride around, pull into the drive, letting the bike drop to idle, then kill and pull the plug--so one is always reading the idle mixture rather than the desired throttle setting. -B. My motorized 2-wheel things: 1969 Yamaha L5T 100cc 2-stroke Enduro (1st bike) 1990 Suzuki GS500E Rat Bike, black with rough edges 2001 Kawasaki W650, Beautiful modern classic    Report

09-22-2007, 6:27 AM Babaganoush Joined on 03-23-2007 SouthCentral Pennsylvania Posts 960 Re: TK CARB MOD REPORT Hi B, You are correct. Jetting is done by throttle position. At the same time, I am watching my tach at the same time for additional info. I am watching to see how the bike runs in third or fourth at wide open which happens to be over 10,000 RPMs. If the bike runs right at WOT, life is good. If not, I've got more work to do. I don't feel the need to do any plug chops. Small engine-one cylinder-one carb: if the engine is stumbling at WOT I don't need to do a plug chop to know it is running rich. Dave "LOUD VALVES SAVE LIVES" -back side of Royal Enfield T-shirt    Report

10-04-2007, 7:54 AM monkeystone69 Joined on 09-18-2007 Posts 1 Re: TK CARB MOD REPORT   I found shims that will work nicely for raising the needle on the Teikei carbs. They are available from an industrial supply house called McMaster/Carr. They can be found at www.mcmaster.com.   The shims I purchased were part #99040A300. They are available in packs of 25 washers. You can order them in varying  thicknesses from .001" to .016". I ordered mine in a .010" thickness. The washers are made from 18-8 stainless steel. They are .125" I.D and .187" O.D.  I paid $7.81 plus shipping for the pack of 25 washers. They fit nicely with no binding.      Report

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