94 sportster

Hi all, new here and looking forward to all and any advice.

Own a 94 sportster, stock except for V & H short shots, thunderslide kit and a SE aircleaner, er and the obligitory bling

Have 40 slow jet and 170 main, get a little hesitation on take off, ie around quarter throttle but fine after that, was thinking of chucking in a 42 slow jet ?

Next question, compression is down about 10lb front and 15 rear, was thinking of just doing a hone and oversize rings if everything else was ok ?

And lastly, very rarely do much out of town riding, hitting roo's is not on my to do list anymore my mate just bought a 08 sportster and drags me off like im standing still,(the *****) is a cam of any value to me, and if so which?
looking for more pickup mostly from around 40kmh to 120 max.

Bez

Welcome to the forum.... is it an 883 or 1200?? With a 40 pilot I'll guess 883 and yeah I'd go with the 42 pilot,2 1/2 turns out with the airmix screw maybe put the stock slide back in instead of the thunderslide(too light)
What are the compression readings?? are you getting a lot of oil blowby ?? 10% variance is OK .
If you have the 883 the 1200 conversion and a street port on your stock heads will leave a lot of people watching your tail light get smaller.
Art is the resident Sporty guru here and if/when he chimes in you can take his advice to the bank.

1200 sporty, very little blowby about normal, the 40 main was the stock jet for this bike and the readings for compression hrrm forgotten but the reading as i remember was as stated, ie 10 lb down on the front and 15 on the rear from manafacture.
Bike still goes well but the mates efi 1200 goes like the clappers and would luv to at least stay up with him

That jetting seems kinda lean to me for a 1200 with a freeflow breather kit, the shortshots aren't really a performance pipe either, stock head pipes and a set of slip on mufflers(cycle shack or SE) would help performance.
I thought but can't really remember that stock 1200 Sporty jetting was 42 pilot and 170 main.
Check this out;
Harley Carburetor Jetting

the manual for the bike says 40 slow jet, pulled jet out and its a 40, main jet is 170.
Noticed a difference pretty much straight away, ie no hesitation from zero throttle to roughly quarter altho it seemed a little slow on the uptake.

Bez

What do the spark plugs look like?? Check your accelerator pump diaphragm for pin holes or tears, do you get a little shot of gas thru the nozzle when you twist the grip??
Does the slide move freely?? Check to make sure slide diaphragm is good too,then get a couple of sets of fresh plugs, put in a 42 pilot and get the idle mix set then go from there,maybe someone with more knowledge or other ideas will chime in.
Good Luck

yup get a shot of gas through the nozzle, 42 pilot jet is in, diaphram i need to check on.

bez

The V&H Shortshots have very little back pressure so you are losing most of the low end torque, good reason your mates EFI sporty is pulling you out of the hole. Cycle shack slip ons with the stock head pipes will do better overall for most street applications and they sound good too. You could actually go up to a 45 slow jet without too many problems. If you have the stock slide, opening up the vacuum hole in the bottom of the slide to 7/64ths will allow the slide to open up a bit quicker but will not cause it to flutter under full throttle. Opening the hole over 1/8th will give you top end problems. Some folks like to remove a couple of turns off the slide spring but I find that the stock spring will work just fine. Either the stock needle from a 98 sporty carb or 1 spacer washer under the stock needle will also help it come off low throttle a bit better. Set the mixture screw at 2 1/2 turns from closed to start out and you should be pretty close to where it will run. A clean Hiflow air filter is a must when doing any of these mods and probably a 180 main jet. This is just MHO but it has worked on too many customer bikes to count and my wifes sporty is set up this way.
If you really want to wake up the beast in your sporty, cams from an older Buell Lightning will bolt right in and boost your ponies up where your friends EFI sporty won't keep up.

Have the thunderslide in, ie light, also the needle is part of the thunderslide upgrade.
Got rid of the stumble from 0 to around quarter throttle since putting in the 42 slow jet, however when adjusting the mixture screw i notice its almost all the way in before the motor begins stumble, have a SE aircleaner on.
This would lead me to think the slow jet is to large or i have damaged the mixture screw ?

Bez

Running true straights on my 05 (Carb) Sporty. Torque Cones, best $26 I spent on her. One of the folks I don't ride with too often actually thought I had done the 1200 upgrade. I don't recall jet size at moment, but my changes are (boy I am going to get bashed here) a 37 model air horn copy (no filter), straight pipes with TCones. She comes out of the hole pretty hard for an 883 with a fatboy (me) on her back. Keep her in her power range and she will climb faster than needed on the street. Idles good, breaks a 100 on the big road no prob. Rebuilt to stock CV40 (other than jets, no springs cut down, no holes drilled out, or any of the other things you read on the net). Took a while to line out, but I am happy with her.

Turn the mixture screw in until the idle speed drops, then back it out until the idle speed drops again(count the number of turns going out), and set the screw in the middle of those two points. The setting is half-way between the point where it falls off either way.

Been so busy messing with a Ford van & other stuff I haven't had the time to check in on fun Sportster stuff & you've already got some good advice, but I'll toss my "2 cents worth" in on a few points:

Baseline carb settings are 42 slow, 175 main & 2.5 turns out on the idle mixture screw. The stock needle is a problem & a favorite replacement for 20+ years has been the N65C, H-D part # 27094-88.

Toss the "Thunderslide" in the trash where it belongs, go back with a stock slide, don't drill it & don't buy a "Dynojet kit" either. "kenfuzed" here has carb kits which I haven't personally tried, but people are happy with & I've looked into - he's doing the same thing the best tuners do - treat the problem(s) rather than the symptom(s).

Don't go there - unless you have a full machine shop or know someone who does. Cylinders MUST be honed with "torque plates" & only a qualifed machinist can do it right.

Short answer - no. Changing cams is ALWAYS a compromise - you must give up one thing to get another & as "mild" as the stock "D" cams are, they do a good job from idle to redline, without peaks or valleys in the powerband along the way. You can target any given RPM band & make more power there, but you lose power elsewhere & the more aggressive you get, the narrower your powerband gets.

Regarding the exhaust, stock pipes with crossover & quality slip-on mufflers is the best you can get for a street/road Sportster. You can tune carb & ignition timing so the V&H pipes work well enough that the "seat of the pants dyno" says they're great & if that's what you like, fine - there's not a major difference, but both dyno charts & speed tests prove what works & what doesn't.

And ALWAYS think "system" rather than indvidual parts - cylinder head combustion chamber, valve size, cam & ignition timing, intake/exhaust, etc. must all work together in harmony & changing one thing affects everything else. Consequently, never make more than one adjustment @ a time, or you won't know which did what.

Yup just finished reading the sportster performance handbook by buzz buzzelli.
Unfortunately it seems like all the info you guys are giving me seems on the money.

Lesson here would be get advice before spending all that money on crap, like i already did, groan

Bez

I’d listen to Art he is the resident Sportster Guru, and most of his advise can be used in theory on big twins or any other motorcycle motor.