I was running out of steam.

[LuckyEddie]

Greetings,
I was running out of steam at about 7 grand. This is a 1980 MNS with pods and a 4 into 1 header. All carb jetting is stock with the exeption of a 47 instead of a 42.5 jet in carb #2. I think that the PO might need glasses.
Anyhow, I raised the floats from 23mm to 20mm as measured from the "in place" gasket and put the needle jets in the third position. The PO had them in the second from the top position (leaner).
Now it makes it to redline though the fuel milage droped to 29 mpg.
It runs fine and pulls hard. It will be a lot of fun. I will run it for a couple of more weeks and then pull it into the barn for a total tear down and repaint and refurbishing (this bike sat outside under a tarp for 20 years).
Life is good.

[CatatonicBug]

Strange jetting setup you've got there. Most run the same jets across all 4 carbs. Having pods and a 4-1 will definitely require a bit of jet tweaking to get it running right, but it looks like you've at least got it useable! Congrats!

[LuckyEddie]

Thanks. I am going to get the correct 42.5 jet and put it in. I can see no reason to have that one jet larger than the other three.

[DGXSER]

Lot os confusion it seems

The PO was probably confused that some bikes came with larger mains in the center carbs to keep those cylinders cooler.

Ummm...you might be a bit confused as well, when you measure float height the spec is based on NO gasket in place. Perhaps that is why you dropped to account for the gasket?

Sounds like you got it running pretty strong. Good luck with the rebuild.

[LuckyEddie]

DGXSER,

I chose not to disturb the gasket, So knowing my previous float height, I just lowered the float height (upside down) by 3mm to raise the fuel level in the carb bowl. That seemed to take care of the fuel starvation that I was experiencing at and above 7,000 rpm. I almost had proof (in writing) of good high rpm running as when I upshifted from 3rd to 5th and let the speed come down from a buried speedometer, I atained the legal speed limit on that road of 50 mph just as a State trooper passed me going the other way.
Further testing in my part will tell me if it will be enough for any sustained high rpm travel, even though that is not my normal riding style.
As for the jet, I think a mistake was made somewhere in history and an incorrect replacement was ordered. All the other jets in the carbs are correct for that year/model. ie 110 mains in all four carbs etc......

[John]

With the changes to the filtration and exhaust systems, you will want to reconsider your jetting. Try increasing the mains by at least one size, and the pilot by at least by one size, then adjust the pilot screw as needed. A second size increase may be needed, but go one size at a time. You should also reset the floats to 23mm, stock setting. You don't say what size mains are in there, you just say stock size jets. Are they 110?

[LuckyEddie]

John,

Yes the main jets are 110's. It runs very very good as it is. Would making an increase in jet size improve the milage? In my mind, pods and 4 into 1 exaust negate milage and encourage performance. Therefore loads of fun and forget about milage. I am not opposed to jet changes and may switch them out anyway. Thanks for the input.

[LuckyEddie]

John,

I am looking into swaping out the fuel jets in the carbs as recomended.
I have located main jets at Z1 at a good price, but no pilot jets.
Pilot jets at another site that I found are going for $7.95 ea. Is that a good price for them? If not, can you recommend a source?

Thanks,

[DGXSER]

MikesXS has them for $6 a pair. There may be a minimum order or shipping cost though. Have you tried a local MC shop or even dealer? They may have them for what becomes reasonable by the time you figure shipping in.

[LuckyEddie]

Thanks for the lead DGXSER,
I just ordered an assortment of main and pilot jets from mikesxs. I like waiting on parts to come, it's like Christmas most of the time!

[LuckyEddie]

My jets should arrive today. I noticed that the needles are the 5 position type but the stats that I have seen show that I should have the other type as this is on an 1980 model. Is the needle taper different from one type to the other? Should I be concerned or leave it as is?

Thanks,