| Author | Message | ||
     Mike_lee |
Ive done some research on this but cannot seem to find my answer, so please bear with me. a 96 S1 with force air filter, after market exhaust (not sure what make but its pretty much a straight pipe after the header), thunderstorm heads w/ NRHS stage 1 head work and N4 cams. I pulled the main and slow jets and saw the slow is a 46, which i think is ok, but the main is a 185. manual states it should be a 190. with these mods, wouldn't you think it should be a 190-195? Elevation here is about 900. I have yet to put any seat time on this bike as I picked it up just in time to store it for the winter so i have not had the chance to do a plug check. | ||
| Buellbum |
good question because my cyclone "coughs" a lot when cold if i don't keep the choke out. it's got high-flow intake and exhaust. there is a receipt for a carb-kit and dynotune so i assumed that the main jet has been replaced with a bigger one. regardless, when i get into that carb, i'm definitely going to go bigger with both the main and slow jets but not sure how big. | ||
| Robertl |
If I remember correctly, my M2 had 42/185. Went up to 45 and shimmed the needle with 2 or 3 washers. Have intake and muffler. 46 would probably be good for what you stated but again that is just a ball park. Doubtful the big jet needs changing unless there is surging at very high rpm or signs on plugs of lean. Buellbum, check the intake seals. I used my choke for years until I finally decided to change the intake seals myself. Man, what a difference. | ||
| Mike_lee |
Thanks Robertl. Ill know more when the weather breaks. If it ever does...ugh! Just thought it strange to see a 185 main (which is even less than the manual states) with the mods listed | ||
| Natexlh1000 |
Are you aware of the forcewinder's potential issues with carbed bikes? Some have a smaller machined opening for the float breather that acts like a vacuum when the airflow is going past. Here is the thread pertaining to that issue: http://www.badweatherbikers.com/buell/messages/384 2/11192.html This info may not be relevant to the thread but I thought you should be aware of the potential. | ||
| Mike_lee |
Nate- I am aware and I hogged that little opening out so it looks just like the photo on the NRHS tech page. The bike did not come with this installed. A much smaller air filter was there when I bought the bike. When I inquired if that small filter was enough, my Netherland buddy responded, try breathing through a straw... heheh That was good enough reason for me to change it. Thanks for lookin out man  | ||
| Buellbum |
i will do so. thanks! | ||
| S1owner |
Get ahold of nhrs they will tell you how to jet it. They helped me. Ir get ahold of Phelan he use to work there | ||
| Mike_lee |
Thanks man.. I will do that. | ||
| Screamer |
Checked on jetting for the 1996 (49 state) S1. Should have been shipped with a 195 main (27275-96Y) and an NOKV needle (27273-96Y) | ||
| S1owner |
I can look tomorrow and let you know what I put in my 96 I have a nhrs top end kit on mine and I jetted it to their recommendation and it runs good. | ||
| Mike_lee |
Thanks guys. I talked with Dan from NRHS and he stated that with the mods listed, a 45/185 would be fine. I could go up to a 190 and it wouldn't hurt anything except mpg. Also mentioned shimming the needle. Ive yet to take the carb out and see if the latter has been done. Has anyone ever seen or had experience with the CVP needle, id like to hear. Seems interesting. | ||
| General_ulysses |
Mike I assume you have the original carb? I have an S1 and am running a Mikuni HSR42. The bike always used to buck, pop and hiccup at low engine speeds with the throttle just barely open. But it wouldn't do that if I opened the throttle up or if I had the choke on. Since it was a problem at the low end of the carb's air/fuel circuitry, I focused on changing the idle jet. (you have to recognize there are three stages with carb tuning: low-mid-high throttle setting, if you don't already know that...and each region has a unique way to tune it). After going a step higher on the idle jet, there was no change at all (and it was richer than most people recommended for the HSR on an S1). Then I tried raising the needle by a clip or two, which barely helped but it still had the problem. After researching it I decided to go with the next step up in richness for the needle. This means the needle is a bit smaller in diameter than the stock one. Because it's thinner, it admits more fuel at lower throttle settings. I popped it in and BINGO, a long standing coughing/hiccupping at low throttle setting problem solved instantly. Just a word of advice to anyone else who may experience something similar. | ||
| Mike_lee |
Thanks GU. Something I don't follow in your response is.. "Then I tried raising the needle by a clip or two, which barely helped but it still had the problem. After researching it I decided to go with the next step up in richness for the needle. This means the needle is a bit smaller in diameter than the stock one. Because it's thinner, it admits more fuel at lower throttle settings." Does this mean you went more than two clips (three?)on the needle? Can you clarify? | ||
| General_ulysses |
Mike - What I was saying is that in order to try and enrichen the lower throttle setting, I lowered the needle clip by 1 and then 2 notches. This raises the needle so that more fuel flows sooner. But this didn't work for me, only having a very marginal effect. I also added a richer pilot jet (can't remember what size offhand, but it was one step up from what everyone else was using with success (and what Al Lighton of American Sportbike suggested I try)). It didn't work either. It still popped, hiccupped etc at low/moderate engine speeds with the throttle barely open. Turning the choke on made the problem go away, but messed up high power setting. So what I did was order the next step "up" in needles to a richer one (again I forget the number). But it was slightly smaller in diameter than the stock one. Since it's a smaller diameter, more fuel slips by it and the bike runs richer in the area my bike needed to run richer. No more hesitation/popping/hiccupping after that. | ||
| Mike_lee |
Ahhh, i get it now. Thank you for clarifying. | ||
| S1owner |
Ok I have the nhrs 1250 kit with 10-1 pistons and stock 96 motor otherwise. I am jetted with a 185 main and a 45 pilot works perfect. I also shimmed the needle. Its basically a very small washer. Cv carbs do just fine through mild builds never had an issue  | ||
| Mike_lee |
Thats good to know Ken. I know this bike has N4 cams which i believe are nearly stock? Your elevation is nearly the same as mine too. Also, i tore into the carb today and found this, which i believe is not stock. I only have minutes of seat time on this bike and am really itching to ride it. Ugh! Its not even February yet.  | ||
| Mike_lee |
Buellbum- Perhaps what the General mentioned would help your issue too. Sounds like the same symptom. On a side note, i had mentioned this CVP needle in a previous response and was intrigued, so i ordered one this morning. Now im wondering if i just wasted $15. Haha Im impatient like that  |
