Rejetting opinion...

Jawknee21

Jawknee21

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In your own opinions, is it dumb or a waste of money to buy a "jet kit"? They supposedly sell the jets I need based on my modifications and my elevation. Is it easier or cheaper to do it another way? I've never done it before so I could end up buying way more stuff than I need...

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The BS34 automagically compensates for elevation. I don't know about the others. You don't say what ya got.
 
83 heritage special. Don't even know what carb I have. And I plan on getting drag pipes from Gordon scott but I'm gonna run baffles too. He gave me an idea where to start but what if it's close but not close enough? I'll be buying more jets and having to wait for them each time in the mail...

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BS34's were stock on it. I would find out what people are using who have a similar setup and copy them. No use starting from square one with a whole box of jets, it seems to me. Maybe buy two or three in the range of the suggested value. Also, with my BS34's I've gotten them so lean it was hard to start and so rich it smoked, just by changing float height.
 
Yup if you customize you get an idea of where to start and change jetting till it works on YOUR bike, there are no magic jet kits. Beware anyone who claims they have one because they have already lied to you. That is what "customize" means. CV carbs don't really "compensate" for wrong jetting they just cover it up a bit. I do a lot of bike stuff but seldom change exhausts because jetting properly IS a lot of work. I buy a lot of abandoned XS650 projects, many of them had after market exhausts, NONE so far have had non stock jetting. Do you think there's a lesson there somewhere?
 
Yep. Nobody can tell you what jets to use besides your motor. You have 5 basic options.
1. Pay to have the bike jetted with dynamometer and EGA. You'll need a new rear tire when it's over.
2. Pay to have the bike jetted by road testing. Since this requires high-speed runs to get things right you'll get either a much bigger bill than option 1. or a slop job.
3. Let a friend or relative who claims to know how jet your bike (but before doing that, I'd suggest you send gggGary a message and find out what he'd give for your bike, just in case).
4. Learn how to listen to what your engine tells you and jet your bike.
5. Leave the exhaust and air box alone.
 
I found out the only way to do it is to test your own bike. I screwed around for 2 weeks before I stopped and read the carb guide, and any other carb info I could get, until I understood how they worked. Then I was able to get it going great in very little time. I have it now so I can run open exhaust or sportster mufflers with a couple turns of the mix screw. Now, it doesn't run perfect with the mufflers, but I can pass inspection. Just shows that jumping around and chasing your tail can be severely reduced by educating yourself and making sure the other systems on the bike are set correctly.
 
So pretty much I shouldn't change the exhaust? How are all these other guys doing it then? Spending a lot of time taking it apart and putting it back together? I knew it was going to be a pain in the ass. There's some people saying, "that's easy" and others saying it isn't worth it. My exhaust just seems too quiet. I feel like I'm gonna get
Run over cause someone "didn't see" me...

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I didn't say that. No matter what you do to it you will have to test it and change things accordingly. There is absolutely no "quick fix" or "kit". Every bike is different.
 
I think you got the idea Jaw Knee it's trial and error tuning with some help here, a bike that doesn't run well or stock exhaust.
 
I farted around with the jetting on my bike for a couple of weeks and this is what I came up with in my situation....

My bike is based on an '82 Heritige, same as yours. I'm running Gordon Scott curved drags, no baffles at the moment, and UNI Pod filters. Stock BS34 carbs. Engine is stock with stock TCI ignition.

I bought the canadian needles and the matching needle jet from Mikes XS. I found these needles/jets worked best with the stock 132.5 mains (after running way rich 1 and 2 sizes up on the mains). The clip is in the 2nd from the top notch.

I then needed to richen up the pilot and currently have a 47.5 in place of the stock 42.5.....I peeled open the air screw ports and have the screws out just about (3) turns. Bike starts about the 3rd kick and runs strong....when it gets hot this summer I'll probably look at it again....for now it works great.

Tom
 
So for the people who have done it, Is it Worth doing? Once you get it right Is there any more messing with it? How long does it usually take to get right?

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Is it worth doing for the sake of making noise? No. I've been in the saddle since 1965 on machines that have ranged from whisper-quiet to raucous. Drivers pay no more attention to one than the other. If you want to wake up the moron in the crusher SUV with cell phone in ear and fingers on pud, keep your eyes open and mount a pair of loud dual horns.
 
+1 on grizld1. I had to do a lot of testing to get my bike to perform the same with mufflers. It ran better with mufflers, than without. Now it runs the same, but louder. I didn't gain any performance.
 
I guess I have some thinking to do. My bike runs perfect with stock exhaust. 1st or 2nd kick start and smooth acceleration. Ive already been without my bike for over 2 months because of powdercoating. I dont
Really want to hassle with exhaust. Even my dad says straight pipes are too loud. You can't hear anything. I haven't been riding that long but from what I hear from everyone else and learn from personal experience is the only person you can depend on is yourself. I'd rather be able to hear other people than expect them to hear me. I guess I really don't know what I want to do now. Thanks guys...

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In fact there's an argument to be made for never using a horn; using the time instead to take evasive action. And from then on slow the hell down....

But you know, I have a feeling that a good tuning might not be a whole lot different from stock. I would see what Gordon says, and maybe not give it up entirely. You can always go back to stock.
 
It's your bike, so that is the best part, you can do what you want. I just advise to understand that there is no bolt-on solution. My bike came with cut exhaust, so I had to deal with that first. Then to pass inspection I had to put exhaust on it and re-jet. If it runs great now, than enjoy the weather. Do the exhaust when you know you have time to mess around with it. I'm getting new exhaust soon. I ride it about everday and it gets really annoying sometimes. Especially around the police.
 
There's a t-shirt out there that i really want to get...

"If loud pipes save lives, imagine what learning how to ride that thing would do!"
 
Oh, I like that one, lol. Another good one I saw at a bike show was "Roll Me in Honey and Toss Me to the Lesbians"
 

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