| Author | Message | ||
     Sarodude |
Ray- Thanks for taking the time! That is too cool. Of course, I wish I could say the same for the weather we're both suffering through in different parts of the country! I will be trying some stuff that I'll post in the exhaust section - likely in a few weeks... -Saro | ||
| Sarodude |
Some information you may be interested in: According to DynoJet, the Emulsion Tube that comes in the Blast jet kit (8111.001) on its own with no other changes would make virtually no difference to the carb. Also, the main jets are cut differently (tapered?) in such a way that they are actually 'richer' than the equivalent number Keihin jet. Needles - given as diameter / distance from tip in inches. The measured points mark the observed changes in taper. Measured by me: Stock Blast Needle (N8EG) .067 / .055 .095 / .720 .108 / 1.280 (beginning of straight section) shoulder: .114 / 1.995 bottom of 'clip': 2.140 DynoJet Blast Needle (DNO870) .036 / .021 .094 / .815 .108 / 1.26 (beginning of straight section) (forgot to measure shoulder) bottom of clip in 3rd position: 2.140 Stock Slide Spring uncompressed length: 5.18 Rate: 1.5 oz / in wire thickness: .029 DynoJet Slide Spring (DSP009) uncompressed length: 4.96 Rate: 1 oz / in Wire thickness: .030 These measurements were taken with WAAAAY less than optimal testing / measuring techniques but they'll give you some ideas in the differences. The 'stock' stuff is off a 2000 Blast that was bought as a demo with 1100 miles. The idle mixture screw cap was missing but the rest of the carb is believe to be original. Notice that, aside from the notably lower spring rate of the DJ slide spring, it will also have less preload since it's a shorter spring. Anyone have anything else they'd like to share? -Saro | ||
| Sarodude |
Man, there's not enough tech stuff being discussed... Has anyone tried ANYTHING other than rejetting a stock carb? For example, a different carb, an aftermarket auxiliary jet (Dial-a-Jet, etc), etc... Nobody's talkin'! -Saro | ||
| Buellzilla |
I got an Email a while back from Force saying that they would soon be selling a ForceWinder air breather system for the Blast, but when I check out their website, 2 months later there is still nothing listed. Does anyone know anything about an air induction system for the Blast from Force Motor Products or any other company? | ||
| Sarodude |
Interesting observation last night... It's certainly one thing to hear everyone say a bike runs lean. Enough people say it and we all wind up buying off on it. Last night I felt leanness in the Blast setup (stock with Bub's exhaust) in a way I'd never felt before as the slide was (probably) transitioning from closed to some unknown position corresponding to just a few degrees of twist on the throttle at a street cruise. Which got me thinking... See this post HERE and spew forth your ideas... -Saro | ||
| Dust_Storm |
Took the bike past the Kawa dealer the other day and asked them some Q's on the carb. Short of tearing the thing off the bike, they couldn't give me a straight answer as far as re-jetting it, though they were optimistic about swapping the jets out with a few 6$ needles and testing it. They said they'd do it for free if I would leave the bike for them to toy with (just don't want my baby to be stuck in the shop for a month while they tinker..) ....Moral of the story - my Kawa dealer rocks, always more than willing to help on a bike that's not even their's. Wish all shops were like that... -=]D_Storm[=- | ||
| Blake |
Hmmmm swapping jets with needles... that's a new one. | ||
| Dust_Storm |
Blake, bear with me, when tired I talk in tounges (and not all of them know mechanics, but they sure know routers!..) I don't even know if that's possible, but it sure sounds interesting.. -=]D_Storm[=- *confused as usual... just pat me on the head and walk away...* | ||
| Snowsrfr18 |
I have a 2001 Blast which I installed a VH pipe, a 170 main jet and a 45 slow jet. The bike starts and idles ok, but I still get a little popping when the bike isn't under load, and when the throttle is closed while riding. Any suggestions? Thanks! | ||
| Blake |
If it's popping out of your tail pipe, you might have an exhaust gasket leak. Check to see if the exhaust pipe's clamp nuts (fasten header to cyl head) are properly torqued. WARNING!!! Before torqing... 1. FIRST loosen the nuts (apply WD40 sparingly to help facilitate removal), 2. Clean the threads, 3. Sparingly apply anti-sieze compound, 4. THEN torque them in stages, alternating from one side to the other a few times before reaching the specified torque of 6-8 FT-LBs, no more! Note, I am assuming, rather dangerously, that the header studs for your blast are the same as the V-Twin Buells. You should double check the torque spec to be sure. Aaron? Can you confirm?  If that has no effect, try replacing the exhaust port gasket between the cyl head and your exhaust pipe. Good luck! | ||
| Blastin |
To avoid being reprimanded by the board anal administrator I will post my carberation question here and my exhaust question in the appropriate area. Can the jets on the Blast be changed without completely removing the carberator? I haven't really had the chance to look at the bike to study it, but I am guessing that it is definetely possible if the air box is removed. Anyone care to negate me? Jerry | ||
| Buellzilla |
Jerry; Check the first message in the archive of this topic. Carburetor, hard to remember the spelling isn't it? Admin got it wrong as well. | ||
| Blastin |
Thanks Zilla. (I wonder if Castlehead had a service manual to guide him along. Judging from his post, my guess is no) | ||
| Blake |
Zilla: Not the admin! Your Blast moderator. Not that I have never mispelled karbarator myself. | ||
| Snowsrfr18 |
I changed the Jets on my carb without removing it. You need a fairly thin flat head screw driver to get the slow jet out, but if you remove the air box and the float bowl it's fairly easy to get at the jets. When you take out the main jet use a open ended wrench to hold the emulsion tube in place, or the whole assembly will come out. I got all of the screws out of the float bowl easily without stripping them, but replaced them with allon head screws anyway per CastleHead's suggestion. He was right that "once is never enough." Good luck with it Blastin! | ||
| Buellzilla |
Blastin; you're welcome Blake; Sorry! | ||
| Dann |
Just got done putting an accellerator pump in my carb. from a used sportster carb. I got on Ebay for $75. Originally I was just going to change the whole carb., but there are some major differences on the carb. body. No place to mount the enrichener or more importantly the TPS. But using the float bowl off of the Sportster carb. with the accelerator pump attatched, I was able to drill the Blast's carb body to accept the sportster float bowl. Suprisingly the pilot holes are already there on the Blast they just needed to be opened up. In all it was a pretty simple procedure it just required carefull drilling, knowing if I screwed it up I was buying a new carb. Throttle response has improved dramatically from the little bit I have ridden, the weather has been crappy in IL lately. If anyone is interested in the details of this mod. let me know I would be happy to post more info. I also opened up the airbox quite a bit, did the usual jet changes and installed a WB exhaust. | ||
| Ezblast |
Dan - if you have the time - could you post the procedure and give us a run down on the differences - a before and after - please:0 | ||
| Blastboy5 |
Jetting made easy? I have a 2000 Blast. just installed the V& H exhaust and love it. I now want to re-jet as this appears to be a good idea. Do I get a Dynajet or Mikuni "kit", or is thais a rip and can I order the 45 and 170's seperately? Can someone clear this up? What do I order and where? I just want it to run stable and strong- I'm so street menace. | ||
| Hoss |
doesn't seem like anybody is really posting here anymore.. but i was curious to see for those who have replaced some of the screws in thier carborators, what size are they? i bought some allen head screws, 10/32 x 3/4 coarse thread but that doesn't seem to be it. does anybody remember their exact specs? also, where can i find the k&n filter i see people discussing around here...is this a drop-in replacement for the airbox or the complete replacement that kinda looks like its for a sportster or something. thanks. | ||
| Xgecko |
K&N makes a dropin replacement for the stock filter in the airbox...it works well. I'll be selling mine when I finally finish my new intake sometime this month. | ||
| Snowsrfr18 |
Hoss, I can't remember which ones I used, They weren't coarse thread. I just took one of the bolts down to Home Depot and got ones with the same thread. Blastboy5 Just go to your local HD dealer, and order a 45 slow and 170 main jet. | ||
| Ezblast |
Help  !I jetted, followed instructions, everything seemed fine,but now I see gas leaking through the front of the carb-the venturi - what did I do wrong?Blasting on the dark side of the dark side! EZ | ||
| Ezblast |
Tweeked the float valve - back to the dungeon - but for a little while she was cooking with steam heat! Blasting on the darkside!EZ | ||
| Davef |
OK, I tried to rejet my carb today. I ordered the jet kit (yes, I know, but I have no clue what I'm doing in there, and didn't want to be popping the bike back together to go get a part and trying again). Let me say, if you are clueless, the instructions aren't much help. I'm guessing the carb has to come off the bike to change the needle? What all gaskets would I need then? Anyhow, I got the float bowl off, and pulled the main jet, and it's a 170. At least, that's what it says on it: a "K" on the top, and "170" on the bottom. I have a 2002. I thought it should be a 165. - dave f. | ||
| Xgecko |
2000 and 2001 Blasts came with a 165. 2002 blasts seem to be coming with a 170. I bought a new carb and it came stock with a 170 main and a 42 pilot. I changed the pilot (to a 45) and put it back together. It runs well (except for the idle on cool mornings which I still have to figure out). I haven't changed the needle yet however I have the parts from my previous carb including a new/diff. needle so I may change it once I move to Japan. You shouldn't have to change the gaskets yet but having them is a good thing. Whether my jetting will work for you I don't know but it works for me at sea level. | ||
| Ezblast |
Blake - Thanks for your advice - I'll try the n65c needle and a 185 main and see where this takes me. Now the million dollar question group for you and Aaron and the rest of the collective Buellers - why does the Blast come from the factory with 170 main while the M2 and 883 both come with 185 main. Is it cam differences - why the big differences on such similiar type engines? Has anyone even tried putting a 185 main in a stock Blast to see what happens? I'm dying of curiosity - Blasting on the dark side! EZ | ||
| Aaron |
The engine is smaller, 492cc vs. 601cc (on a twin, the carb feeds two cyls, but only one draws at a time. I have verified the jetting on the Blast with the a/f monitor. Trust me, it wants a significantly smaller jet than a twin. Having used the same HSR42 on half the XR1000 motor as well as the Blast, both highly tuned and using a short drag pipe, they want pretty much exactly the same jet. | ||
| Buellzilla |
Hey Aaron, Have you by any chance compared a/f readings using stock exhaust vs aftermarket and stock airfilter vs K&N or homebuilt air cleaner. When you say that you've verified the jetting, should I assume that you've verified 170 main and 45 slow jets? | ||
| Aaron |
No, I never used the a/f meter with anything resembling a stock Blast motor. I *did* tune it up when stock and I seem to remember the factory jet was close. But remember I'm at 5300'. My comment was based on literally hundreds of dyno pulls on this highly-tweaked Blast motor (both with and without the a/f monitor), plus the work I did on the similarly tweaked XR1000 motor, plus the many many 1200cc twins that have been on this dyno. With an HSR42, the Blast and the XR wanted jets in the 145 range. A typical stockish 1200cc twin with slip-on and air cleaner wants something more in the 152.5-155 range. A really hot 1200cc twin like my M2 wants to be in the 160-162.5 range. The one 88 incher I did was around a 170. The 100" race motor only wants in the 150 range. But it's got a Thunderjet, which is designed to supplement the main jet at high rpm. My whole point was that based on what I've seen, I would expect this little Blast motor with it's stock CV wants a smaller jet than a simlarly tuned 600cc cylinder with the same carb. |
