Cv carby

hi mal here i ride a 99 model dyna wide glide 56 k onthe clock 88 cub i have recentley had the cams changed to aset of s@s 510 gear driven cams seams very good my problem is i have had the cv fix up with the thunder slide kit the jeting size are the poilet is 48 and the main is 175 it is real good up top but it runs like **** down low i forgot it also has a hyper charger and aftermarket pipes :witsend: thanks mal from australia

Pilot jet seems to big to me...try a 45 or 46 pilot jet.
Others that know more than me will be along with some suggestions as how to dial your carb in. Good Luck:devil:

1) Get rid of the Thunderslide, go back with the stock slide & don't drill it out. The idea is to make the slide raise quicker for better throttle response & it will raise quicker - but then it "hunts" - moving up & down always trying to find the right position, which it never does.

2) Slow jet is too big - you probably need a 45 for that application. If it was me I'd get a 44 & even a 42 to try, but a 48 is definitely too big.

3) Main jet is too small. I can't tell you what the best size would be for your bike, but for example, a 175 main is the baseline for a 1200 Sportster with stock cams.

Assuming you were dealing with the dreaded "carb farts", that's almost always the needle & I like the N65C (H-D part # 27094-88). "kenfuzed" here has a carb kit with a similar needle that's machined better & although I haven't tried his kit yet, I understand what it does & it's what the best tuners have been doing for years - fix the problem rather than put a "Band-Aid" on the symptoms.

You're "on the needle" almost all the time & if you look @ dyno charts with the air/fuel ratio graphed, you'll see a spike in the 2500 rpm range - carb goes way lean. Messing with the slide, changing the spring, going up on the slow jet, etc. does not fix the problem - the needle is the problem. A bigger slow jet turns the spike into a bump & while the "seat of the pants" dyno may say the problem's gone, it's not & I can see it on the real dyno.

You can get the kit from "kenfuzed", or just get the N65C needle from a H-D dealer (about $8 U.S.). Get the low end dialed in & then try different main jets to see which one your engine likes the best - I prefer the engine to tell me what it likes rather than me telling it what it ought to like. 2.5 turns out on the idle mixture screw is your baseline & you shouldn't have to go more than 1/4 turn either way from there. And if adjusting the idle mixture screw while the engine's running does next to nothing, that almost always means the slow jet is too big.

ok fellows thank you you have given a lot of imformation to work with ////the dyno i dont know //i think i will try and have a go at it my self // i will keep you posted as i go thanks mal

Do you have any problems in the midrange? - Dyno testing is done for full bore apps (top end -max torque) but how often do you run wide open?
A dyno is nice but tuning for moderate speeds will give you what your looking for.

yes it dose feel jumpy at mid range

The dyno operator is key - most run full-throttle from 2000-2500 rpm to redline, but you do not have to do that. We've done several tests with several bikes over the years, including runs up thru the gears @ part throttle, holding a steady rpm @ like 3500, etc. - trying to get as close as we can to real world conditions. Of course the dyno does not take "wind resistance" into account, but you do not have to put the bike in high gear, crank the throttle wide open & see what the max HP is. You do want to do that & if the dyno has an air/fuel ratio "sniffer" attachment you can learn a lot from a full-throttle run, but it won't tell you what's going on under the part-throttle positions you normally use & rpms you normally run on the street/road.

A really good dyno operator can get pretty close though & sometimes they'll have you ride the bike - run it like you would out on the road & the operator will watch the computer screen. You can get several chart print-outs under varying conditions & then you can see what the engine is doing. Carb slide's not working right, jetting is wrong, ignition timing is off, etc. Dyno won't get you to perfect, but it'll get you pretty darn close - if the operator knows his machine & how to use it.

And there in lays the problem - How many good DYNO men do you have in down under land. Probably only at a dealer; but you might get lucky if your can find a good shop in your part of the world that has a DYNO.

had the same troubles with my thunder slide so bought a new original slide from dealership then added this tuner kit at harley-performance .comStage 1 Carb Tuner Kit

Came with all parts I needed and now never think about bein out of tune only think about riding

you are right in my area there is 2 to dyna tune shops witch i have to travel 2 hours to got there you ring up to get help and they do not want to give any advice the same old story bring it down and we will have a look not happy with some work man ship that i have go so i am going to have a go at it my self //a dyno here cost me about $460 plus all the exstras /the really good ones are in sydney witch is 4.5 hours from home

You should be able to get the idle & low rpm range dialed in & then you can do "roll-on" tests. Just pick a straight & level stretch of road where you can run full throttle in high gear for a long way without getting in trouble - you'll need to make the same run many times & it wouldn't be wise to invite the police Pick a point A & a point B - cruise along normally to point A, nail the throttle @ 50 mph & hold it to point B. How fast were you going when you got to point B? Notice any hesitation, "carb farts", etc.? Establish a baseline making the same run @ least 3 times before changing anything.

You can do it 4th gear starting @ 40 mph if there's not a good place to run the bike that hard in 5th & looking @ the SpeedCalc program, @ 5500 rpm in 5th gear an FXD would be going 129 mph. Very few Harleys will pull to redline in high gear, but the point is you're making your own dyno & if you can run say 50 mph to 85 mph over the same stretch of road again & again, you can use the "roll-on" tests give you a lot of info.

Once you establish a baseline, just change one thing & make the same run again - if you make more than one adjustment you can't be sure which one did what. And although today's gasolines with detergent additives make spark-plug reading difficult, you can do a "plug chop" if you're on a road where there's a safe place to pull off to the side. At full throttle & at the end of a run, chop the throttle, pull the clutch in & hit the kill switch all @ the same time, then coast off to a safe place. Pull the plugs & see what they tell you. Make whatever adjustment you think you need & go do it again.

Also, roll-on tests take into account things the dyno does not, including aerodynamic drag on you & the bike. Doesn't count for much @ low speeds, but once you get up to highway speeds it certainly becomes a factor. You can learn a lot from roll-on tests & although it'll take time to get the bike dialed in, you can do it without going to a far-away dyno & spending a lot of money.

Sounds just like what the doctor ordered. I put my Dyno stage 1 kit in and am having trouble getting the idle to settle down (found out what the problem was and now I've lost top end power. I can get it up to 80 mph top and have no power after that.
Gonna grab a couple extra sets of plugs and find a place to test it out. See if that don't work.

Oh boy - Just what I needed - Have the new slide and don't have it installed yet. The Wifey got me on a honey do list so long I think she's in leaque with the anti-bikers of the world. But I shall overcome - Helps when ya got a bunch of grandkids that are trying to get on Gramps good side now that riding weather is here.:roflmao: :roflmao:

yeap you are right about the marriage bit i have changed the needle setting to riching it up changed my piolet to 46 main to 185 took the vacum off the hyper charger keep the flaps open all the time know as i speak to day the bike seems to preform at both ends of the scale when you sit down with a stubbie of beer and think and ask a few questions and take note of people helping i think that i have marsted my problems ok so it took a few days but when i am not to good at this sort of thing it worked out well i would like to thank all who put some in put into my problem thank you you have saved me a lot

Put the new slide and changed the one washer on the main jet last night and checked the carb over while putting it back together; everything was working per the manual. Took it out today and scared myself half to death. My baby can roll with the big boys again.
No carb farts -accel was great all the way to redline; no pops on decel and top speed increased to 105 from 80. All in all; I would say the beast is ready for summer.