Just rejetted, new problems

[trbig]

But with individual pods, he should be up 3 sizes anyway

Just one size is plenty when adding pods. I don't know where they came up with that. It doesn't lean the mixture out that much. In many cases, the stock air box breathes better than the pods due to air flow disturbances around the engine. That list is kind of a guide to go by but in no way is a bible. I would think a K&N filter in an airbox would require more jetting than the pods would.

Just me personally... but I'd add two sizes to a 115 main, leave the pilots stock and see how things are there. I'm running K&N style pods with mufflers drilled out some and one size up on mains was plenty. My headers don't blue or yellow, so I must be pretty close.


Tod

[TopCatGr58]

Okay, you've got 2 jets in sizes 110, 115, 117.5 and 127.5 .

I'd pull the 127.5's, swap the 117.5's into the location of the 127.5's, and put the 115's in where the 117.5's are now!

Then IF you don't have the brass pilot screw caps OFF, then you could try the stock pilots. The mains will give you more richness in the range you will probably really want it, 4K and above rpm!
T.C.

[BlkMage]

Originally posted by TopCatGr58
Okay, you've got 2 jets in sizes 110, 115, 117.5 and 127.5 .

I'd pull the 127.5's, swap the 117.5's into the location of the 127.5's, and put the 115's in where the 117.5's are now!

Then IF you don't have the brass pilot screw caps OFF, then you could try the stock pilots. The mains will give you more richness in the range you will probably really want it, 4K and above rpm!
T.C.

Actually, I have 4 115s, and they are in the main slots now, stock pilots. She sounds a bit better, road test tomorrow. I hope this clears it up, need the bike ready to go to the Reno Air Races friday after work.

[trbig]

Just wondering how they determined you were running way lean in the first place? Are your pipes turning yellow or your plugs have really white ash on them? Is it simply because you have these "Extras" and didn't re-jet?

If it was running good to begin with and the plugs looked good...

If it ain't broke don't fix it! (As I prepare to disassemble a running motor to mix and match parts... hoping to make it run MORE betta!..lol)



Tod

[BlkMage]

Originally posted by trbig
Just wondering how they determined you were running way lean in the first place? Are your pipes turning yellow or your plugs have really white ash on them? Is it simply because you have these "Extras" and didn't re-jet?

If it was running good to begin with and the plugs looked good...

If it ain't broke don't fix it! (As I prepare to disassemble a running motor to mix and match parts... hoping to make it run MORE betta!..lol)



Tod

Both problems. Bluing pipes and white plugs. People at the Tahoe rally told me that I should fix it soon.

[Hired_Goon]

Originally posted by trbig


Just one size is plenty when adding pods. I don't know where they came up with that. It doesn't lean the mixture out that much. Tod

In my case, trial and error proved Denny Zanders calculations to be spot on.

My symptoms were lack of power and severe pinging when opening the throttle. I went up through the jet sizes one a a time and each time it produced a hesitation or splutter at a different rev range.

It still runs a tad lean and I reckon I could go up one more, but it runs so well I don't want to touch it again.

An interesting comparision of airbox vs pods by my understanding is, pods have less restriction per carb so therefore more fuel has to be added to the flow to compensate. It can draw air anywhere from a 350 degree raduis without restriction.

With an airbox, regardless of what filter you use, there is only so much air can flow in through that one opening tucked under the seat. Changes to filters only means a very minor change to jetting as the airflow change is minimal.

I know opinions vary on this but I can only promote what worked for me.

Edit: There does seem to be a trend with different models though. Older standards seem to tolerate bigger changes better but changes to the specials don't seem to be as big. Maybe this is related to the different year carb setups?

[BlkMage]

Just ran a test ride with the 115s and 42.5s, not good. Seems like my over-rev and backfire problem is coming back. Would it be such a crime to go back to stock? I really need it running tomorrow.

[scott0757]

You could try it original jetting) and drop a heat range on the plugs..., but if it's really that lean running, I'd leave the 115s in there and open the pilot jet screws another half turn.
If the backfire is on deceleration, it's running on the pilots and is too set lean.

You did say you checked the timing and vacuum advance, right. May need to retard the timing a bit...

[BlkMage]

Drop heat on the plugs? How would one do that? When I was buying the new plugs I was offered hot or cool plugs and got the cooler ones. And I don't think I can adjust the timing on my bike, it's an '81. And I really don't want to mess with those screws right now as I have no way of fixing if they go too far out.

Anyways, it ran in the garage with the stock jets, taking it to work tomorrow.

[BlkMage]

This makes no sense...

Ok, back to all stock jets, rode today to work. Keep in mind the ONLY things I've messed with since Tahoe rally (where it ran great) are jets (which are stock now) and the idle screw. Somehow, my over-rev problem IS back. I've pulled the screw down so far there's almost a half inch between the screw and the arm it pushes to adjust idle, it's still there. I hope someone can help me within the next little while, or it'll have to stay home this weekend .

[TopCatGr58]

Hey Mage,

You are changing too many things at a time!

Okay, you had the 45 pilot jets, and the idle was okay, no high rev problem! But it ran poorly above idle with the very large jets!

Then you put the smaller 42.5 pilots and the 115 jets, reported that your hi rev problem was back, but you didn't state much about how it behaved in the mid/upper throttle response? IF it behaved okay there, then it sounds like it was just a bit lean in the pilot.

But then you put ALL STOCK back in, 42.5 pilot and 110 mains! So it is still lean in the pilot/idle circuit, and now also probably more lean in the mains!

IF it behaved okay in being able to run to redline with the 115's, then put them back in, and the 45 pilots.

Remember folks, he can't adjust the pilot SCREWS because the brass caps have not been removed, IIRC!
T.C.

[79XS11F]

Make sure your butterfly's are not hanging up and re-sync the carbs. The only way for it to fast isle is for it to be getting more gas and that typically happens when it's getting more air. Make sure the cable is not hanging up as well and check for air leaks.
Rob

[Jeremy_Sells]

Vacuum Leak

Hey there - CV carbs will gain idle speed whenever there is a vacuum leak. You have had the carbs off and on a few times now, so make sure that you have all of the vacuum lines hooked back up and that there are no cracks in them from taking them off and on several times. I forgot to notice if you have a Standard with vacuum petcocks, but if you do, make sure that the diaphrams in each petcock hold vacuum when you draw/suck on the petcock's vacuum nipple. If you have a Special, make sure that the diaphram in the octopus is not leaking by using the same method I just listed for checking the Standard petcocks. My diaphram in my Special's octopus was shot once and my bike would overrev, especially when hot. Took me almost a year of dealing with that issue before I stumbled on the problem. Verify NO vacuum leaks, re-sync with a vacuum gauge and you should be golden! If you want my opinion on jetting up a modded 11, send me a PM!

[BlkMage]

Originally posted by TopCatGr58
Hey Mage,

You are changing too many things at a time!

Okay, you had the 45 pilot jets, and the idle was okay, no high rev problem! But it ran poorly above idle with the very large jets!

Then you put the smaller 42.5 pilots and the 115 jets, reported that your hi rev problem was back, but you didn't state much about how it behaved in the mid/upper throttle response? IF it behaved okay there, then it sounds like it was just a bit lean in the pilot.

But then you put ALL STOCK back in, 42.5 pilot and 110 mains! So it is still lean in the pilot/idle circuit, and now also probably more lean in the mains!

IF it behaved okay in being able to run to redline with the 115's, then put them back in, and the 45 pilots.

Remember folks, he can't adjust the pilot SCREWS because the brass caps have not been removed, IIRC!
T.C.

A bit off there TC. The whole time I had the 45 pilots in, I had low-end issues. Some other time I'll try with the 115 mains and stock pilots, but right now I need to get the over-rev issue fixed again. And you are right about the brass caps still being there.

[TopCatGr58]

Originally posted by BlkMage
Just ran a test ride with the 115s and 42.5s, not good. Seems like my over-rev and backfire problem is coming back. Would it be such a crime to go back to stock? I really need it running tomorrow.

A bit off there TC. The whole time I had the 45 pilots in, I had low-end issues. Some other time I'll try with the 115 mains and stock pilots, but right now I need to get the over-rev issue fixed again. And you are right about the brass caps still being there.

Hey Mage, I was just going by what you said in an earlier post, that's why I thought you had switched to the leaner 42.5 pilots when I thought you had gone up to the 45's and had mostly gotten rid of the hi-rev problem!? Keep at it, jetting can be a trial and error process!
T.C.