There are plenty of threads here on this stuff. Just use Google.

Check out the link. I showed you. I wrote some on the process myself last night for another fellow who's been having trouble.

First you need to buy some stuff, and get it on the way. Use Mikuni brand (other brands are sometimes numbered differently) main jets (152.5 and 155 would be good--no smaller than 150 at the most), a bigger idle jet (55, I guess), and get some #4 washers for the mod. There are some guys on Ebay, like Niche Cycle, who have good deals on Mikuni jets. You can grab them all up and combine shipping, I think.

You could also check around the bike shops. Don't discount Harley shops as they fool around with Mikuni carbs as well.


You might be able to do some of it without removing the carb. For the idle jet, I don't know. Removing the carb isn't too tough. I've done it a couple times at least. It can be a little aggravating. It helps to remove the top of the carb and the slide before removing the carb. Remember not to booger up the slide (the rubber diaphragm/cylinder/needle thingy. It's delicate and expensive to replace.

It's hard to tell exactly what's in the bike already. Someone else could have rejetted it. If you're cheap, and you don't mind having the bike apart for a while, you could take out the main jet that's in there and see what size it is. That will give you a clue as to whether the mixture has been messed with or not.

Can you find the idle mixture adjustment? On new, unmolested bikes, it is actually covered by a brass plug which must be drilled out. If you cannot find the mixture adjustment, that is a clue that the jetting has not been messed with, or messed with properly, at least.

I am not an expert. I have never run a straight pipe on my bike. I am giving you numbers based upon my experience reading here. Feel free to look for carb tuning threads here. There are more than one written by several moderators here. It's a BIG topic.

What elevation do you live at? The higher you are the smaller (leaner) jetting you will need. Sea level or below sea level will need big rich jetting. Your climactic conditions play a role. Humidity and temperature make a difference.

I personally live around 1500 feet elevation (It's mountainous, so it's variable). I run 150 main with 3 washers. The bike runs great, but mpg isn't what it used to be. I have the stock muffler, but plan on installing the Dyna muffler, though.

I reckon the Savages from the 80's used a 152.5 main with the stock muffler, but I'm not exactly sure everything else was the same. The carb was approximately the same, with minor differences. One I know of is that the slide did not need the spacer mod because the needle was adjustable. . Screwed that up for us, didn't you, Suzuki?

Anyway, a 155 seems like a good place for a straight pipe and performance air, but I'm not a carb expert. If you want to tune it in, you should get two or three different sizes and test each one. The way to test them is with sustained full throttle at highway speeds.  Most people here don't go any bigger than 155, so you could try a 152.5 as well if you want to be conservative.

The 55 idle jet is one size larger than stock. Some people can use the stock size, as the mixture is adjustable, to a point. When you need more than 3 turns out on the mixture screw, though, you'll need to go a size larger. Whatever idle jet size which gives you close to 1.5 turns out on the screw at its optimum mixture should be the best size to use.

With a bigger jet, you won't need as many turns of the needle. With a smaller one you'll need more. If it's too small, you'll have to turn the needle till it risks falling out. If it's too big, you 'll have to bottom it out to get the right mixture. Neither is good.

Actually, it looks like the old Savages used 155 mains stock.  

I live in charlotte NC. The carb has been messed with by previous owners. The brass cap the covered the enrichment knob has gone. I adjusted it up back by 1/4 turn yesterday and rode and it seemed better and less backfire on deceleration.



So I could, in theory get the 152.5-155 jet and 55 jet and set up on step 6 of the diagram? And that should in theory provide a better running bike.?

Counterclockwise...
It was maxed clockwise wouldn't turn any further.

I edited my last post.

Since this bike seems to have been down the road as far as mods go I'm going to say you should pull the carb, go over everything...there are lots of helpful links here to get you going.

This was the first bike I ever owned and yes, it can be intimidating but it becomes a useful skill to have.
Just remember to go slow, document everything (take pics if you want) ensure you can go back to the settings you have now.

When I first removed my carb I was freaking out...but after working on lots of carbs now they actually are very simple....first thing to do is find out what size jets are in there and understand what they do.

Best advice I can give you is to go slow, change one thing at a time and make sure you can take it back to where you are now. If you decide to pull the carb the first thing I would suggest is to not change anything...just get in there and clean it really good, put it back together and see if it's fixed...could be just a clogged jet but at least you'll know what jets you have at that point.

The jets are marked...of course i have to use a magnifier to actually see them...lol

i'm wondering if you can actually post a picture of the vents/vac port...how did the PO plug the vac port? Did he experience any of the problems you've had?

It's good that you know the PO...he may have some insight.