uchi

i was at my buddys palce today whos doing the work to my bike and we fired it up, runs pretty good but lean, shes a little poppy with the choke in, but when we pull the choke almost all the way out it free revs cleanly. i did a quick search through here but didnt find my answer, so im asking it, how much should the fuel screw be turned to compensate for the adjustment the choke gives?

also she fired right up today in the cold, first shot, no choke, just touched the button and she started and idled great. jet kit made a big difference i think in how well it starts. also with the new exhaust and it being cut and jet kit it almost seems like shes revving up a bit faster than she used to. could just be in my head. and il have to get a vid or sound clip for you guys, the cut jardines sounds amazing. very angry, very in your face, very mean. just a fantastic growl to it

last thing, as im sure the regulars will read this, in another post i asked about the fuel level, john cleaned the connectors out for the level sensor and the fuel guage started working again

uchi

Anyone ? We have no carb tool so wed like to get it as close as possible without removing the carbs too many times

Little_Horse

Did you change the pilot jets too?

And to try and answer your question on the mixture screws right around 1 and 1/2 turns or 540 degrees seems to be the norm around here.

I have tried 48 pilots which for me where way too rich so I switched back to the 45 pilots and my screws are at 1.75 turns now. Basically you are trying to find a setting that the bike does not search for a consistent idle, but still will start when cold and start when hot. If it does all those things just be on your merry way.

Cheers

RK1

Standard pilot screw setting per both the Honda service manual and the Dynojet instructions is 2.5 turns out, 2.75 for California bikes.

Some people run less, but when I tried 2.25 after rejetting my Ca. bike it wouldn't idle without the choke even when it was warm. Went back to 2.75 and all was well.

If your pilots screws are too tight it would produce the symptom (needs choke to rev) you describe. But if it's so lean it needs choke to run good, seems unlikely it would start from cold without choke.

uchi

I cracked and bough the tool today. I can't remember how many turns she's out but it fires up first shot while cold and after warming up it started no problem aswell. Just stumbled while being revved. The bikes exhaust was replaced with a pair of shortened jardine high mounts k&n filter and the pair system was removed. I know that the filter people often say they have issues with it. But when I bought the bike the filter was on already and it ran perrfectly fine.

Thanks for the help

One more thing. If we get it running smooth and clean is there a point in dyno tuning it? I know with a car I'd have it tuned with a wideband on the rollers and have the afr set for it. But people here don't seem to get into much dyno tuning from the sounds of things so I'm wondering if its worth any kind of gain over just having it run smooth with a street tune

lazn

A dyno tune probably could improve things even more.. But how much time and $$ do you want to put into a few HP is up to you.

uchi

thats what it comes down to. if it runs good im happy to ride it and beat up on it, but if its gonna cost me 500 or 600 or more to get another 1 or 2 hp then ill toss that idea out the door and just run it the way it is

Tweety

With a K&N in there it's a really good idea to put it on a dyno, add your custom pipes and a jetkit with unknown setup and it's an even better idea...

But you are completely right... If you get it to a decent setup as is, you might get 2-3 bhp more when having it dyno tuned... Not more... There are no "free horses" in the VTR, just waiting to be unleashed as in some cars/bikes where a simple setup makes a world of difference and the stock setup is "bad"...

uchi

Good point. I think I'm gonna ditch the filter put in the paper filter again just to be safe. See how it runs from there and play with the fuel screw.

There was a place that I wanted to visit but I've heard some horror stories from a few people now. One guy brought in his sled to get the carb cleaned out and picked it up with no rear track and some other parts removed and a 400 dollar bill. Others had similar stories. So ill just ask a local forum I'm on for a shop. Thanks for the help

sweetriden76

+1 on the dyno, especially with a superhawk

It'd be almost impossible to get it right without some dyno time, even if you think it runs good, I spent a whole day on the dyno at work with mine and still had to go back another day and drill the pilots on size up, I used a #77 indexed bit, you can feel it stick in the pilot jet, like it almost goes through but not quite...thats a trick we picked up tuning honda shadows, I forget where my mains are at, I think they are one step leaner then stock, I know the dyno jet kit was way way rich where they suggested at least for the atmospheric conditions here in central PA, when we first fired it up it was nothing but black smoke and would hardly run...now it's absolutely perfect with a K&N, DJ kit, and my two brothers slip ons with about 6 inches cut out of them...it was 101.4 at the rear wheel and with the 36,000 miles on it I think thats a fair number, dynos can vary a bit, actually a lot, and it depends how its setup, ours is setup to not inflate the numbers at all because we really don't care, we are in business to tune for ride-ability not to see who can make the biggest number on the screen

uchi

good to hear man, we actually followed the dj instructions for setting up with a k&n and shes still a little on the lean side. were assuming the pair system may be the culprit or just because the cans have been shortened or even a combination of both who knows. trying to find a tuner around here is a bit of a pain in the ***. the one guy i wont go to even though people recommend him, ive heard enough bad things to stay away from him, worst case scenario i just keep playing with the screws till it feels good and leave it alone from there

sweetriden76

yeah, a lot depends on atmosphere and also every bike is different, I doubt PAIR will effect it much, mostly that just makes decell popping, since it allows clean air into the exhaust to help burn off emissions, basically the emissions regulations mucking **** up again, I'm not a fan of emissions reducing stuff, its almost always detrimental to horsepower

VTRsurfer

I had a tech, Nigel who owns a shop in Laguna Canyon (Samurai Moto-Sports and Racing) adjust my pilot screws. I don't have the tool and he used to own a SuperHawk. I've probably adjusted more idle mixture screws on cars (several thousand) than him, but I trusted him.

The correct procedure is called "lean best idle":
1. Turn screw in until idle drops.
2. Turn screw out until highest idle speed is just reached.
3. Repeat for other carb.
Usually requires some back and forth to fine tune it.
You can use a tach or a vacuum gauge to get highest reading.

Mine ended up at about 3 1/2 turns out on the front and 3 3/4 on the rear. That was at about 2 miles inland from the Pacific Ocean, so basically at sea level.

I still get the very rare carb fart and stall at idle, but it's much improved. At 6,000 feet it doesn't like to idle, but I don't do too much idling at that altitude anyway.

I shimmed my needles .020" 6 months before the pilot screw adjustment. Stock cans and air filter.

uchi

good to hear thanks for the info. i can use just your basic vacuum guage from any parts store?

gixxerjohn

we will jsut toss it on the dyno on the way back to your place, should be 1 hour to do it, so prob 80 bucks to get her tuned up nice

Tweety

If we are talking about the carb sync yes, a standard vacuum gauge is just fine...


John, keeping in mind that you obviously knew more than we gave you credit for the last time around, I'm still gonna stick in one advice... If the VTR is tuned on the dyno like most operators do without thinking/asking ie they tune for the top end (correct for an IL4) the VTR becomes twitchy and full of holes in the midsection... Not so fun... Tune for upper half of the midrange to be peak, and sacrifice top-end if neccessary to get it smooth all the way... You will like the results better uchi...

uchi

Thanks for the advice tweety. Have I mentioned yet how much I hate carbs? Lol

gixxerjohn

100% i told my friend who is a superbike builder, and he knows how to tune the twins, he tuned my tlr back in the day, obviously in the IL4 we want max hp at top end, but the twins are always about solid low end grunt and mid range pull.....


so i spoke with him already and he said 1-2 hours MAX to get it spot on.... which isnt bad if you ask me.......


and thnx for that, nice to hear someone actually stepping back and admitting they spoke out of turn

thnx

Cheers

Tweety

Heh... dunno If I agree 100% with your wording, but OK...

My general warnings of knowing who you are dealing with when wrenching on your bike still stands... You however turned out to be an OK guy, as far as I can tell knowledgeable and with a decent sense of quirky humour (fit's right in with this bunch of misfits... ) And for that I respect you... And when I'm wrong I say so..

I never ever said or will say that I know it all... I'm still learning... When I stop learning I'll stop wrenching...

As I didn't know how many v-twins you have played with in the past, I was just pointing it out to save you some trouble and time... It seems a common mistake, dyno guys just tune to top end/top power (possibly cuz the customer doesn't know better either in some cases?) and that makes the VTR a rather booring companion...

Tweety

Heh... I like carbs... They do what I tell them too... the electronic boxes in some other bikes gives me fits though... I hate any chip I can't re-program to do what I want it too... Not what some engineer and lawyer in Japan decided in a commitee it should do...

uchi

lol, thats why reprogamming the computer is nice, at x rpm with x throttle position i want this much fuel and timing, heres a wideband, ill drive around, you self learn, ill fine tune. so much easier

john good to hear you found a guy, guess i wont have to mess with your blacked out visor after all, lol.

looks like ill be using your guy, is he around you or in the gta somewhere?

gixxerjohn

on your way home, so wont be an issue

uchi

Ill probably come back to visit him in the spring. Would like to get her tuned on a warm day after the winter