T1 I have V&H straight shot pipes replace the tensioners with gears and have a Andrews 37 cam with Arlin Ness big air sucker breather. stock needle the dynojet needle didn't hear too many nice things about.

just did a long ride and the mpgs went from 49.8 to 40 mpg?? this cv40 is driving me nuts!! although the hiccups are now at idle and start off verse starting acceleration.. not sure which is worse?

 

no leak from there..

 

LOL. Good thing I like eggs because my face is covered in them right now... Should have asked whether it was TC or Evo before I opened my mouth

I'm admittedly and willfully ignorant about TCs but know those carbs fairly well. I don't think you're too far off on the jetting where you are now or maybe even where you were. I'm just guessing but especially with the drastic drop in fuel mileage I'd be considering timing (advance) as a possible issue. Evo uses a VOES, yours has a manifold pressure sensor that sorta does the same thing. If it's leaking, sticking or otherwise not dong right, that'll cause all kinds of weird readings by the ECM pertaining to ignition timing.

My apologies for "stepping in it" earlier and I've no idea whether the manifold sensor is an on/off or variable resistor type but I'd try to verify it's working correctly before dropping $$ on a new carburetor.

 

t150vej brings up a good point: the MAP sensor on the top of the intake manifold. When I did the top end rebuild on reaper this past summer, I found mine in 2 pieces. It broke off at the nipple that sticks into the manifold. Another thing he mentioned that is worth looking into is the slide diaphragm. If torn, or perforated, it will make the carb act weirdly.

This was my MAP sensor:




Cheers!

 

Crap.. Should have said it's an 01 TC, bought more gaskets today going to try the intake gaskets and if that doesn't work it's a mikuni time...
I have to ask timing? I know that I can't hook up my timing light like I do my car? Wouldn't that have more hesitation in acceleration if it were off?

 

Do you know what ignition module you have? If it's the factory one, I'm not sure if it can be remapped. If it is factory, and can't be modified, you can always get an aftermarket module (if it doesn't already have one), such as the Daytona Twin-Tec TC88A (which is what I have in Reaper), and get the cable, and free software download to make adjustments to the ignition timing map.

Do check that MAP sensor on the top of the intake for cracks, before pulling the trigger on a new carb.

Cheers!

 

Honestly I never paid attention to the object on top of the intake.. I know that all of my cars have them.. Didn't think the bike had one.. I will definitely check out the MAF sensor.. Makes since thinking about it now..
I had a dynatek ignition in it but wasn't a big fan of it, seemed like I was eating plugs with it and couldn't get it dialed in properly, so I went back to the stock one.

 

Just to clarify. We have a MAP (Manifold Absolute Pressure) sensor in the intake, not a MAF (Mass AirFlow). The ignition module uses the info from the MAP sensor to apply the advance settings in the ignition table. Id the MAP sensor is cracked, or broken like mine was, it will cause an intake vacuum leak.

With your engine, intake and exhaust mods, you need a programmable ignition module. The stock module with the factory table(s) won't be right for your build. I would recommend the DTT TC88A, and a good dyno tune. I would bet that will solve your issues.

Cheers!

 

Clammy thanks for the advice, going to try the intake gaskets first and roll from there. When I was spraying it for leaks I did hit that pretty good, I know it wasn't leaking there yet, but most likely will after I replace everything else...

 

Alright alright alright...... Replaced seals, and found an open vacuum tube on the backside of the carb... Plugged it and only got one hicup. Waiting for a nicer day to put some miles in the seat to check out the mileage and see if there are any more hicups... Hope not.
Or it will be kuni time
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