| Author | Message | ||
     Muckerpuck |
crap i get like 45 mpg.. but i ride like a lunatic.. and you must be way lean to run 75-80mpg , and you dont nessisarly lose performance with lean conditons, somtimes you gain performance at the cost of engine damage. (Message edited by muckerpuck on March 20, 2008) | ||
| Xgecko |
wait until winter ends the alcohol content will go down but yes I to get about 7-11 few miles per gallon now than I did this time last year because of Ethanol | ||
| Swampy |
61 MPG is something I would love to get, I figure I am only getting 45-50. To improve it you would want to go back to stock carb settings, but with it you will also have the corrosponding, hard starting and poor performance. So you will have to balance it all out. | ||
| Yttikcat |
Hi everyone, I have not been on the site for a while, but still have my blast and it now has over 8,000 miles. By the way, I got the service manual for Christmas. As far as gas mileage, I think 61 is good. That is about what I get. | ||
| Xgecko |
summer mileage used to be worse than winter though I have seen high 70's in the summer on a 157 miles gas station to gas station run....scared the crap out myself because I had left the petcock on reserve so I had no idea how much was in the tank...it was nice to find out I only needed 2 gallons...the advent of ethanol has screwed up my whole tuning strategy...and forced me to use a 180 main in the winter 60 is about all I can get | ||
| Muckerpuck |
hey everyone ,, and ez,, where ya getting your parts from these days,, ez your doin lots of shoppin chicago hd right.. thats not to far from me,, im gonna get the jets id didnt get last year ,, go from the 45/175. and pick up the 48,180.... i did find i new hd parts site. Adventure HD http://www.hmhd.com/index.asp they accept paypal and have a very nice parts system. i entered 27165-90 any they told me it was a 48 slow jet unlike most online harley parts stores... and some of those silly mirror plugs.. and if i dont say their part number maybe bullistic will chime in with his i know all the part numbers bullstick (Message edited by muckerpuck on March 23, 2008) | ||
| Imadreadhead |
Check this airfilter out. expensive but cool http://cgi.ebay.com/ebaymotors/CV-Carburetor-Air-C leaner-for-Velocity-Stack-Harley-HD_W0QQcmdZViewIt emQQ_trksidZp1742Q2em153Q2el1262QQcategoryZ35574QQ ihZ015QQitemZ250218380620QQtcZphoto | ||
| Ezblast |
I have two different parts lists at my yahoo site - lol - thanks for that link - yeah - I do Chi HD pretty heavy due to 20% off internet orders - pays for shipping most the time and still a good deal to boot - not a shot at the sponsors here who are known to go out of their way to get a part for a customer - thanks for that link - I have been looking for a better part lookup reverse with description - I think you found it - so thank you. EZ | ||
| Ezblast |
Dread - my stack filter filters better, I ran that sponge foam type on a set of Webers with stacks on a VW Bug - lol - they are pretty restrictive and hair and fine material still find there way through - particle size allowment still to large - mine is 0.025 - which is pretty minute. | ||
| Muckerpuck |
i thought it was an iteresting find my self also...... | ||
| Ezblast |
 Putting it here so it can go up there - if you see the screw right below the top cover on the side - a philips - it holds the throttle bracket(as does the top corner screw)that is the one I slotted and loosened - then I did the top. Don't forget to tighten it or it will mess with your throttle response and you'll get backfire and a badly running engine. EZ (Message edited by ezblast on March 27, 2008) | ||
| Muckerpuck |
8. Perform float level check as follows: a. Place carburetor on a clean flat surface with the intake manifold side down. See A of Figure 4-20. b. Tilt the carburetor 15° to 20° in a counter-clockwise direction until float comes to rest. See B of Figure 4- 20. NOTE The measurements will be incorrect if the carburetor is tilted less than 15 ° or more than 20 °. c. Using a dial vernier caliper or dial caliper depth gauge, measure the distance from the face of the carburetor flange to the outboard edge of the float. Be careful not to push on float while measuring. d. If the measurement is between 0.413 inch and 0.453 inch (10.49 -11.51 mm), then the float level is within specification. Proceed to step 9. e. If the float level is not within specification, remove the float, and referencing the table below, carefully bend the tab slightly to adjust the float level. For example, to increase the float measurement, bend the tab toward the carburetor body. This will have the affect of decreasing the amount of gas in the float bowl after assembly. f. Install float and check float level again. Repeat procedure as necessary until float level is within specification.  | ||
| Ezblast |
 shall be added to the top. EZ | ||
| Muckerpuck |
way better size than cardomain gave me,, thanks ez.. need any other pics photshoped let me know | ||
| Gbaz |
is there a place to get the carb to intake gasket online? I wanted to replace it when i have everything apart, but cant seem to find one at the pars places i usually use (google is not helping...) | ||
| Ezblast |
Any of our sponsors or my fave - Chicago HD EZ | ||
| Buuueller |
Have any of you had this happen? I have a random problem of starving for fuel at high speeds (70+). Sometimes it keeps pulling until I let off but at other times I hit about 75ish and it completely dies until I let go of the throttle. Then it runs just fine. It is as if the bowl runs dry. Its happened before and after Harley repaired a carb flooding prob, so I doubt they did anything. Im sure its just the float (which Ill check this weekend) but I thought Id pass it by the experts to see if yall ran across anything else causing this. (Message edited by buuueller on April 11, 2008) | ||
| Reuel |
I might have had similar problems. HEET fixed it for me! My brain is going around this whole rejet thing. So, for the first bit of throttle, say, up to 1/4, the slow jet is providing fuel. As I open it past that point, the needle is responsible for the majority of the mix, plus the slow jet, of course. The main jet is responsible for WOT and near WOT. Now, the question. How do the needle and main jet relate to each other? If someone shims the needle, will WOT become richer as well? If the needle is shimmed well, will a shim have to be removed if he puts in a bigger main jet? I see lots of details on what to do, and how to do it, but what I really want to know is, with details, exactly how does each change affect other fuel circuits? | ||
| Buuueller |
There is a great color picture at the top of the page of a carb break down and how fuel flows at different throttle positions. Most of what you described is correct. The slow jet (small number) is all alone. The main (larger number) jet provides with an open throttle. Vacuum at WOT causes the needle to move up off of the main jet to allow the fuel to flow. The shims placed under the "head" of the needle has it sitting higher and makes it start to move from a higher point than the stock possition. This starts it farther from the main jet allowing easier fuel passage. Dont confuse the bowl needle with the main jet needle like I did. And there is no perfect way to tell if all circuits are working together properly without an air fuel ratio meter or a dyno tune session. But these guys have it pretty well figured out for this bike. (Message edited by buuueller on April 11, 2008) | ||
| Reuel |
Thanks. I wasn't sure if I was correct. I plan to get an O2 sensor setup next time I have money. Until then, I have to use the seat-of-my-pants method. Or, I could put my ignition prototype in and just measure acceleration, make changes, and measure again. Details at 11.  | ||
| Gbaz |
i did not think about the O2 before i had my pipes coated, or ide have one now  i was thinking of trying to shove a 3 wire o2 sensor up the tail pipe just to tune and then remove... | ||
| Buuueller |
Just make your own A/F meter with radio shack parts... under $10. http://www.markvanderkwaak.com/dbbp/tech-tips/mm.h tml | ||
| Gbaz |
the meter is not the problem for me, its mounting the O2 sensor. | ||
| Gbaz |
just bought a Gunson EXHAUST GAS TESTER/ANALYZER off of ol ebay. anyone know off hand what the air/fuel ratio should be for a blast? I seem to remember 15 as the desired number. Need to read up on the testing process now, and see if i can tune idle/ 1/4, 1/2 and full throttle with this thing. | ||
| Ezblast |
14.5 | ||
| Reuel |
15 for economy, but the Blast already gets great mileage. 14.5 leans just enough to the rich side that you get better power, but don't kill gas mileage. Or, in fewer words, "What EZ said!" | ||
| Gearheaderiko |
15? I think that would be a stock Blast. 14.5 is 'ideal' (I might be wrong-I've done that lately). 13.5 gets more power consistently (from my tests) and even as rich as 12.5 will see gains (but not always). Your results will vary depending on engine setup. For instance pulling off the air cleaner got more power while giving a higher a/f ratio (further testing was not done though with the filter off and a richer mixture). | ||
| Gbaz |
the charts say 14.7 is the magic number for max power, but you need to run richer jic you get a sudden lean condition for some reason (so you dont melt a piston). I need to do some checking. I know you can set idle with no problems, i just need to see how to do 1/4, 1/2, and wot. I dont know if u can get a good reading with the bike under no load. The parts for me to make my new intake just came in. so i hope to get everything tuned for dorking around town.  | ||
| Gearheaderiko |
The bike has to be under load for accurate readings besides idle. If no load readings worked and 14.7 was truly optimum for power, then we wouldnt need dyno's. As far as 14.7 being 'ideal' I can only go by my dyno readings. If you want power you'll need to go richer. If you want mpg, then go lean. What 'charts'? | ||
| Gbaz |
Theres a lot of info out there on it, here are a few links from a quick google. the last one is different, it actually gives 14.7, but then goes on to say for max power use 12.5 - 13.25. Every engine will be different, and without a real dyno run your guessing, but setting the A/F ratio is about as all im willing to do until i finish with mods. Then spending 200-300 for a dyno tune would be worth it. http://www.motec.com/support/manuals/Manual%20AFM1 %20A5.pdf http://www.engr.colostate.edu/~allan/thermo/page10 /page10.html http://www.experiencefestival.com/a/E85_-_Technica l_details_on_Air_Fuel_Ratios_required_for_burning_ E85_gasoline_and_ethanol/id/1345236 |
