LC4 Power restrictor

[re-entity]

Sorry to resurect an old post. Bomber posted this some time ago:

Carb;
There's an emission control device on the right hand side of the carb that opens a port at the top of the diaphragm when 2nd or 3rd gears are engaged. This allows the pressure to equillibrate with the atmosphere and retards opening of the slide. Removing this device and blanking off the port (with a 3/8th's vacuum cap, if my memory serves me correctly) improves throttle response in 2nd and 3rd.

A few questions...
Is this mod different to removing the power restrictor?
If not, what does that involve?
What is a vacuum cap, where do I get one and how much do they cost?

[speaksgeek]

Me too, where will I find the vacuum caps?

I've already pulled off the plug, but I could use that space under the tank for other bits of fun.

[Bomber640]

Power restrictor? Do you mean slide stop that reduces the total kW? We didn't get those here to the best of my knowledge. I think they were for European markets, where some riders are only allowed a limited power/weight ratio (like in NSW). There's no power restriction device on my 640 other than the emission control device (maybe also the snorkel in the airbox).

The emission control device on the carb is a solenoid that opens a port at the top of the diaphragm when 2nd and 3rd are engaged. Because it's vacuum from the engine that opens the slide, releasing some of that vacuum to the atmosphere slows opening of the slide, and restricts performance (as well as emissions). If you remove it you'll probably have to re-route the other port (with a little disk filter on the end of the hose). This lets air move in under the slide as it opens. Blocking this off could also slow opening of the slide (arguably). I rerouted mine to behind the rear brake master cylinder.

Vacuum caps are just sturdy rubber caps, and can be got from car parts places like Repco etc. They cost $1-2 each. I also used one to blank off the speedo drive.

[agent34]

Go the Flatslide and take it off when you sell it !
Leave the other shit on as it does not hurt it.

3 cents.

or go to ktm talk for some good tuning advice on BST 40's. guys there swear by the mods they do and seem to get them going similar to the FCR.
4 cents

[speaksgeek]

I just removed mine. Nice and clean without it, the caps are 10mm. Found mine at Autobarf.

Next step is a dyno session. Get it jetted properly for the open side cover airbox.

[SMC690]

Just let me know when you plan on it Angus if you want some Dyno company.

The little caps off the breathers on new bike batteries also do the trick for blocking CV's.

Stuart, I have researched a few of the mods for the CV for interest sake and will let you know what I know on Saturday. :)

[Wobbly]

Dyno schmyno - just break out the hole saw and a box of beer :)

[Daws]

I am planning on a Dyno run before I make any exhaust mods - Bikes & Bits in Brighton anyone?

[Wobbly]

Speak to the hand ... coz the head don't have a bike to ride on :roll: :lol2:

[re-entity]

My bike was originally sold in Perth so I'm wondering if power restrictors might be required there???

Thanks Bomber and Justin. I might have to pop the lid on Sat and get you to show me what I have to do.

[speaksgeek]

I was planning on going to Dynoverks. They quoted me $100 for a before and after power run + jets cost + jet changing time.

Seemed fairly reasonable.
I'm loath to put my open side cover on until I have the nice big jets in there - I ran my last bike too lean and it went schput.

Thinking might try and aim for early next week - but open to suggestion.

[Wobbly]

Shouldn't be able to rev the ktm enough to make it go bang if its running lean....

[Sibbo]

Shouldn't be able to rev the ktm enough to make it go bang if its running lean....
:poke: :laughing_sign:

[speaksgeek]

I was thinking about trying to book myself for dyno and airbox jetting session on monday or tuesday... anyone got opinions on Brighton Bikes vs Dynoverks?

Anyone want to come?