Doc OK Doc I'm pretty sure I'm doing the numbers right, check my math...89 miles divided by 4.2 gallons of gas equals 21.19 miles per gallon. Not a big deal to ask that I double check the calc...the most obvious things sometime are overlooked.

Now the good news is I think you were right...there was another problem. I finished putting my carb back together...used a 170 main, clip on third slot for needle, started at 2.5 turns out on the PMS...AND I put three layers of Liquid electrical tape on the crack on the intake manifold and here's what I got. Eventhough I leaned out the needle setting, the plugs are now showing much richer than before...I used to be on the 5 slot down(richer) yet I had plugs that were white. Point is I'm 95% sure the crack in the mainfold was allowing air to enter from the manifold bypassing the carb and leaning out the mixture. No other explanation why the plugs would have been showing white before on the 5th slot?

So I'm going to get a new manifold and put the clip on the 2nd slot to further lean the mixture and see what happens. Oh and the bike is definitely making more horsepower. Thanks for all the help. I've learned alot. I may make a jetting chart showing what happens when you change different jets and if you put pipes or an air cleaner on...it might be good to post to the site and so others can see what I've been looking at myself trying to figure out my problem. Is there anything like that on the site that you know of? I'll send a very rough draft so you can see it. PM me with your email.

There needs to be a well thought out chart, based on mods, carb settings, altitude, gas type, 1up/2up. Base everything on a couple of brand named jet kits. (2 or 3 charts). But most importantly we should have seperate charts for 1600's and 1700's. If you guys get the info, (survey members that do their own carb work or know which ones are missing out of their kits ) I'm sure that there would be no shortage of frustrated volunteers to crunch the numbers and graph it out. Thanks for the website guys.

If you think the manifold has developed a leak you can try to temporarily fix it. Try using some of that marine goop or shoe goop. Can't guarantee it will hold up to the heat but what the hell.

Doc

Doc, I sealed up the crack in the rubber on the manifold with "liquid electrical tape". The stuff comes in a can and has a little brush. I buy it at West Marine Products and it made to seal electrical connections in marine environments. You can do multiple layers to build it up...so far I'm running richer eventhough I moved the clip up two notches(leaner). I'm still not getting a tan plug so I'm going to go one more notch up and see what happens.

Also as far as a chart I'm starting one for the 1600's. I don't have the numbers for the 1700's.

Well an air leak will make it leaner and difficult to tune.

I would not play with it much until you get the new manifold ... just not worth it ... unless you want to do it as a learning experience.

Doc

The plug reading is "only" gonna give you a reading of what the engine was doing when you shut it off.

I quit tryin to read all that stuff and just go by how my bike is
running.Here`s a good page of info
http://weislake.com/sig/mucker/instructions.htm
I still have alittle backfire on hard decel,but I`m tired of lookin
for it.Bike runs good And my pipes are a nice grey from all the
jettin and rejettin I`ve done Truthit ain`t flat here

The backfire on hard decel is not unusual. If I rev mine up to almost redline and then quickly back off I sometime get a backfire.

If it's popping on decel as you slow down (around 2000 rpm) then turn the PMS out 1/2 turn.

Doc

I`m right at the end doc 3 1/2.And the 37 pilot of course is too big.
If I`m correct doesn`t that denote an exhaust leak.I sealed all my
exhaust joints with hitemp silicone.It`s more like a soft bubble most of the time at slower rpm with an occational pop.I don`t think it`s leaking
at the heads,I`ve looked for residue with Qtips to see if I could find any,clean.The only place I can`t quit get to to seal with silicone is the
cross overpipe.No residue there either.(I least I think you`d find residue of some sort if you had a leak) As always,bike runs good

Exhaust leak is more like backfiring .... especially if it's large leak. If it's quite small you could get popping but I find it's usually the PMS.

Try 1/4 out anyways ... if it goes away then you know it's not an exhaust leak. I find the PMS popping is usually just before you downshift, around 2000 rpm.

A soft bubble is the pipes .... that what they sound like.

Yes .... it you have a leak you'll eventually see black residue.

Tough to nail it down for you without hearing it.

Doc

You should just put the dynojet kit in and follow there instructions. It sounds like someone did the bak and compensated with a needle adjusted to the 5th ring. Check the dyno kit and see if they only used the needle out of it. But why is the starter jet plugged? OH WAIT WAIT WAIT. Did you do the choke knob mod?????if its sticking out, That could be your gas mileage alone.