Disabling the 3TJ restrictor

[plodder]

I recently bought a 3TJ and it's great but a bit lacking at the top end.

I am guessing that this is due to a top speed restrictor in the clocks that I have read about.

Is there any way to work around it without resorting to the mechanical mph/kph device on the speedo cable or buying an aftermarket or 4DX ignitor box?

Does anyone have any general information or wiring diagrams of the restrictor and how it works?

Thanks.

[Taggyd]

the easiest way is to get an M-Max box, small thing that plugs behind clocks sorts everything out without the fuss!

[Evilchicken0]

Actually the easiest way is to fit a KMH to MPH converter box. The restriction comes in at 180 kmh and as this will be converted to 180 MPH you'll never hit the restriction.
You have to fit a GOLD box that goes at the bottom of the speedo cable. (Blue ones at the top won't lt you fit the top fairing on).

But you say lacking at the top end so I doubt this is going to do that much as you'll be at 112mph which is license loosing on a motorway.

[plodder]

Nothing to do with public roads. Track time, innit

I'm just too used to my 1000EXUP's indicated 176mph top end (-10% speedo optimism).

[Evilchicken0]

Well these engines are 40% of the thou. They rely on corner speed and handling rather than torque so the whole style of riding is different.

[tiptop]

is ther any other way of de-restricting them? im building a track/race bike 3TJ so dont want it restricted.

i would be totally doing away with the speedo drive assy and the speedo clock etc...will that do any thing?

[plodder]

Well these engines are 40% of the thou. They rely on corner speed and handling rather than torque so the whole style of riding is different.

Yeah, I'm having to recalibrate my brain. Overtaking when there are only small gaps in oncoming traffic is a pain in the ar$e without the torque. The 1000 just wafts past. Problem is the 1000 is leary in the corners and I wanted something sharper.

[Evilchicken0]

Here's the ways to derestrict in order of ease / cost.

The restriction needs to be reset at 0kmh each time the bike is started up or it will restrict to 12,500 rpm in every gear. The speedo also needs to register a speed or again it will restrict to 12,500 in every gear - remember that when you take it to a dyno.

Road bike - KMH to MPH mechanical converter.
Pushes the restriction to 180mph effectively removing it. Your speedo reads in mph, which is a bonus but the sweep of the needle is reduced.

Road Race bike - M-Max (or similar) derestriction box.
Plugs into the loom where the speedo restriction wires go (behind the speedo). This disables the restriction. I've heard of them plugging in under the saddle too.

4DX CDI - the official or european spec CDI had no restriction. Some 3TJ2 SP's were also imported and deresticted and all the 2TK 1WG's are unrestricted as they're built before 1988

Deresticted CDI 1WG - I've seen them on e-bay from the far east I don't know if they work.

BDK CDI - Full race CDI with slightly revised ignition map. Expensive but should work well with the other BDK mods

[Evilchicken0]

Yeah, I'm having to recalibrate my brain. Overtaking when there are only small gaps in oncoming traffic is a pain in the ar$e without the torque. The 1000 just wafts past. Problem is the 1000 is leary in the corners and I wanted something sharper.

You need to change down 2 gears on these which is a pain but you get used to it. Ride the bike as a 400 and they're one of the best bikes arround - especially for money. Sort out the handling before you look for more power, you'll soon get used to it.

[plodder]

Hehe. I've put a 89-90 FZR1000 front end on it with the 400 fork tops to get the length right.

R1 brakes & 320mm wavey disks so now stops a treat

Also stuck a 07 R6 shock on it using that adapter the bloke from Shetland sells.

And stuck some some Avon Viper Supersports.

It handles like it's on rails & stops sweet as.


So what does the restriction do when you get to 112mph? Does it limit revs to 12500 or does it cut a cylinder off etc.?