[Boismier]

Has anyone tried the T-Mod for CV carbs done by Tracy Spencer at V-Twin City? Apparently he takes your stock carb and reworks the fuel circuits to improve response, and reduce carb farts, etc.

 

[Keepmvng]

You haven’t indicated what modifications you have done to your engine or what bike you have.

The T-Mod for CV carbs is nothing but a gimmick that theoretically makes massive improvements. A total waste of money.

Get the jetting right first.

Assuming that you have added SE air cleaner and after market mufflers, there are three things you need to do to your carb:

1.Adjust the idle mixture screw out another ½ turn (2 turns total). To do this you need to drill the cap off the idle mixture screw so you can open it up.

2. Replace the #42 slow (pilot) jet with a #45 to cure any off-idle stumbles or backfires,

3. Change the main jet a size one or two larger to offset the leanness created by the free flowing intake and exhausts. If you have changed both intake and exhaust, A #180 jet size should work

Keep

 

[hdxlr8r]

Is that personal experience or opinion on the T-mod. According to the article in Hot Bike (april2001) some of the modifications are explained. And why would I go to a 180 main jet when the factoy put in a 190, I think it is already lean enough.

 

[HIPPO]

I have no idea because I do my own, but I have heard that they work very well from others that know what they are doing.
All the professionally modified CV's work very well but the end result always depends on the person doing the final tuning on the bike.
If anyone thinks they are going to be dialed in by mail order they are dreaming. Too much difference from bike to bike.
The professionally done CV's just have more "potential" then a stock one. Wether the increased potential is worth the cost is another story, and probably would depend on the capabilities of the end user.

 

[HIPPO]

To answer the specific jet question, jet size only has meaning if everything else stays the same.

Once you modify the needle taper and/or the airbleeds, transitional behaviour changes drastically. In it's simplest form you would run a much smaller main jet with the richer Dynojet needle.

 

[hdxlr8r]

I guess I missed the part about the needle change or modification.