amorti wrote: My information is based solely on my research of CB-1s, I know nothing about nc30's! Have a look at the gearbox in your speedo and report back.

LOL OH! , will do! haha

An alternative is to fit a Sigma bicycle computer. They can measure up to 200mph. Calibrate it to the size of the front wheel while you're sitting on the bike. It's much more accurate than an analogue speedo, and much lighter too.

On my RVF I found (via my Zumo) that having a rear 40T sprocket and a 160 rear tire has conveniently made the KMH speedo read 100% over the true MPH (i.e. 100KMH is actually 50MPH). It's to the point where it's within a 1mph at all 20 KMH intervals. :)

Got it sorted today using gearing commander, took note of an RPM and my displayed speed then ran it by gearing commander to work out the difference was 12.4%. So at low speeds its almost exact but I found when doing 160 its reading 180 and because I am still waiting on my CDI to arrive the 180 limiter kept kicking in haha

DrunkenMistake wrote:Got it sorted today using gearing commander, took note of an RPM and my displayed speed then ran it by gearing commander to work out the difference was 12.4%. So at low speeds its almost exact but I found when doing 160 its reading 180 and because I am still waiting on my CDI to arrive the 180 limiter kept kicking in haha

I was pretty close then!

Did you look at the gearbox on the back? If yours is 1:1 as standard then a cb-1's 11:12 reduction box would reduce the error to @3%, which I'd call negligible.

Why not just do the resistor mod to beat the restrictor?

tanto wrote:An alternative is to fit a Sigma bicycle computer. They can measure up to 200mph. Calibrate it to the size of the front wheel while you're sitting on the bike. It's much more accurate than an analogue speedo, and much lighter too.

link

mo haggs wrote:

tanto wrote:An alternative is to fit a Sigma bicycle computer. They can measure up to 200mph. Calibrate it to the size of the front wheel while you're sitting on the bike. It's much more accurate than an analogue speedo, and much lighter too.

link

http://tinyurl.com/3qxwe92

Cru Jones wrote:

mo haggs wrote:

tanto wrote:An alternative is to fit a Sigma bicycle computer. They can measure up to 200mph. Calibrate it to the size of the front wheel while you're sitting on the bike. It's much more accurate than an analogue speedo, and much lighter too.

link

http://tinyurl.com/3qxwe92

very good - but wich one is best for motorcycle use?

mo haggs wrote: very good - but wich one is best for motorcycle use?

Good question. I'm not sure if any is really good for motorcycle use.

^^^
The BC800 and BC1200 seem to be the most popular fitments but they've both been discontinued. Although the 800 and 1200 both appear to still be available here along with the 700.

There's some fitting guides here and here.

Wiggle mention on their site that all the new Sigma Sport computers have a speed range up to 199 km/h, I dont know if that's correct or not as Sigma dont mention maximum values on their site.