MACs and Re-jetting an 84 VT700

[rpneal44]

Well, got my MACs installed and the sound has been mellowing quite well. Recently I have noticed a discoloration of the pipes around the down-bend at the exhaust port. I'm assuming this is due to a lean condition, and re-jetting is in order. So I have a few questions:

1. The service manual states that the stock main jet is a #120. What would be the recommended step up in jet size? #130? #140?

2. Is the float bowl the only thing I will need to remove? (I'm guessing not as usually larger jet = new needle)

3. May I assume that I will need a carb gasket set? Or is it okay to reuse the old ones if I'm careful not to damage them?

4. Are there any specific tools I should have on hand other than the standard (ok, Metric) sockets and wenches n stuff?

5. How much would the VT700 procedures differ from that of the 1100 in the "Jetology" sticky?

6. How should I expect the larger jet to affect performance or fuel consumption?

I may have more questions later in the process but I want to have the tools and parts in order before I turn a nut.

Thanks in Advance

[rat]

1. The service manual states that the stock main jet is a #120. What would be the recommended step up in jet size? #130? #140?

You can go up in much smaller increments than that, if I recall. I seem to remember running 118s in mine.

2. Is the float bowl the only thing I will need to remove? (I'm guessing not as usually larger jet = new needle)

Aside from the breather, tank and carbs themselves...Yes. Remove bowl. Replace jets.

3. May I assume that I will need a carb gasket set? Or is it okay to reuse the old ones if I'm careful not to damage them?

If they're fine, resuse them.

4. Are there any specific tools I should have on hand other than the standard (ok, Metric) sockets and wenches n stuff?

You'll probably need picks for the gaskets.

5. How much would the VT700 procedures differ from that of the 1100 in the "Jetology" sticky?

haven't read it.

6. How should I expect the larger jet to affect performance or fuel consumption?

Bigger hole... more fuel goes through it.

I may have more questions later in the process but I want to have the tools and parts in order before I turn a nut.

Before you do all this, do a chop test. If that shows a lean condition, then you need to rejet. Chances are you're only gonna need to adjust your idle mixture.

[bondo]

My son's '84 has MACs and the headpipe on the front cylinder is discolored too. I have seen lots of bikes with this discoloration and believe that it is pretty normal for these kind of pipes. His bike was popping on deceleration and I adjusted the two mixture screws to 3 1/2 turns out. Very little popping after that.