Triumphrat

5bassman · 11-25-2006

What is the purpose of the Restrictor plate and what will it do for the bike to remove it?
If remove, must you rejet?
Is this almost as good as removing the Airbox?
Thanks!

vertwrks · 11-25-2006

My guess as to the why would be with the stock pipes etc the restrictor would help low end or midrange performance. Once you add free-er flowing exhuast you need to open up the intake to let more air get to the engine to take advantage of the free-er flowing exhuast. I took my restrictor plate out today and with the stock air filter I didn't notice any difference but as soon as my UNI filter comes in I expect it will make more of a difference. It is about time I took full advantage of my pipes! If you have stock pipes I doubt you would get any benefit from removing the plate.

From what I have read here It seems that the K&N pods flow better than K&N filter in the stock airbox, I am certain by next spring I will have gone with the pods because I have the disease that it seems so many of us have, you can fix something that is not broken!

RedBird · 11-26-2006

I wouldn't remove the restrictor plate unless you have free flowing silencers. Yes, once you remove the restrictor plate AND have free flowing silencers installed, you must rejet (and possibly shim or change to richer needles) to get the fuel/air mixture correct. Until you get this mixture correct, your bike will probably not perform any better than stock and possibly worse than stock. When I installed the NARK with NH Toga silencers, mine ran about like stock with 140 main jets and Thruxton needles. When I put the 150 main jets in, it really turned on at higher rpms. The 790's respond very well to free flowing silencers and a lot less intake restriction, IMHO. I never removed the restrictor plate--I went straight to the NARK; however, once jetted properly, one should get good performance gains from restrictor plate removal, IMHO.

Larry

FattRat · 11-26-2006

Alrighty then,

I did 22,000 miles on a 790 with D&D pipes, a K&N air filter, expensive NH bellmouth, and some Thruxton needles,
BUT the ristrictor plate was removed.

I've since done 600 miles on my current 790 with the same D&D pipes, same K&N air filter, same NH bellmouth, and the same Thruxton needles..........
but with the restrictor plate still in place.

The following is my conclusion, make of it what you will:

With the restrictor plate removed, throttle response is improved. But she needs to be spun up with enough air moving into the air box for everything to be married and work in concert. The engine feels like it has more *punch* when the conditions are right, but THAT'S what makes this combination left for lacking..... conditions gotta be 'right'.

If you're tooling along in a high gear at cruising speed, but not fast enough to be forcing air up the throats of the carb's..... and you grab a hand full of throttle, the engine reacts in a fashion similar to "turbo lag"..... a slight delay before the party. I would not have been able to identify this "lag" had I not ridden my current bike with it's restrictor/divider plate in place.

With the plate in place, the engine is more user friendly, the power more docile and linear, and more responsive to throttle input when you're just tooling along at legal speeds in a higher gear. I don't feel any loss of power in the broad scheme of things, and when I researched the various recommendations for jet size with the plate removed, they didn't call for larger main jets unless there were additional factors in the changes being made.

Bottom line, if you live in the 'party zone' of your tach while chasing little Honda 600's through the canyons, and you don't want to go to the expense of an air box elimination, a restrictor plate removal will give you more (felt) throttle response, but it won't give you significantly more power.

At least, that's what I've concluded.......
and I'm leaving mine in. If you wanna tear your air box apart to get at the plate, you may as well remove it and install pods.

[ This message was edited by: FattRat on 2006-11-26 11:58 ]

5bassman · 11-26-2006

Thanks guys! Good stuff to think about.

Brooksie · 11-26-2006

Take a sawzall to the air box and get it out of there! The air box removal system is the way to go. The bike revs so much smoother and gets to the power (what there is) quicker.

JMV2006 · 11-26-2006

Mods to my T100

Initial configuration:
- AI removed
- Baffle removed
- Added .020" (0.51mm) shim under the carburettor needles

Dynotest Results (values at the back wheel)
1st run:
Power 60.6 BHP at 6,831 RPM / Torque 67.4 Nm at 6,062 RPM

Second configuration:
- Snorkel removed
- Thruxton carburettors needles
- 116 Main Jet
- K&N Air filter

2nd run:
Power 58.9 BHP at 6,986 RPM / Torque 69.0 Nm at 3,562 RPM

Third configuration:
- Air Box Restrictor plate removed

3rd run:
Power 61.3 BHP at 7,295 RPM / ]Torque 71.3 Nm at 5,769 RPM[/b]

Below you can see the comparisons:

First and second run

First and last run

5bassman · 11-26-2006

So do you feel like it was worth it from first to last run?

[ This message was edited by: 5bassman on 2006-11-26 13:28 ]

JMV2006 · 11-26-2006

Definitely!
The figures and curves talk for themselves.
I did 5 dyno tests in total and this is the best configuration for my 2006 T100.
- AI removed
- Baffle removed
- Air Box Restrictor plate removed
- Snorkel removed
- Thruxton carburettors needles
- 116 Main Jet
- K&N Air filter

Soon I will write what the mpg with this configuration is.

5bassman · 11-26-2006

Quote:

Soon I will write what the mpg with this configuration is.

I'm really interested in that. My bike runs great for me with BC Predators,AI removed. I have a chance to pick up the Airbox Elimination Kit at a great price but I don't want to mess up a good thing plus dump alot of money into something that might not benefit me(but maybe others). I'm not a racer, just a cruiser.