Rev counter reading wrong!!

[Jeppo]

Basically my rev counter is reading about 2-3K above what the engine is actually doing. At 80mph it is reading around 12k as opposed to 9 (i'm running 14/45)

It revs all the way to 17k no problems (obviously my engine isn't capable of this) and there appears to b no limiter but i can't be sure. I think my limiter is raised (there is a little box on the back of the counter that says limiter raiser on it lol.) and i have hit the limiter before so there used to be a working one.

Another thing is that when i pull the clutch in doing about 80mph the revs drop and it just dies, no other problems to report....what could be the problem do u think?

[masterofinsanity]

usual rev counters indicate a problem with the battery, does it start ok?

[cargo]

I suspect the little black box is some kind of derestrictor....................... that would appear to be completely removing the rev limiter...as opposed to just the 110mph restriction.

I'm betting your bike is an import ?

[Jeppo]

I did think that but it starts absolutely fine hot and cold.

Yes it is an import cargo, but it has an mph converter which means it doesn't need a derestrictor, though i suppose that doesn't mean it doesn't have one aswell.
And I think i've hit the rev limiter once on track, though it didn't bounce like a normal limiter should it just dropped the revs back a couple thousand...

Either way this problem has only just started, the counter has been fine the last 9 months.....Haven't ridden it 2day but i was on it for a couple hours yesterday and it was like it since start up...

[cargo]

I did think that but it starts absolutely fine hot and cold.

Yes it is an import cargo, but it has an mph converter which means it doesn't need a derestrictor, though i suppose that doesn't mean it doesn't have one aswell.
And I think i've hit the rev limiter once on track, though it didn't bounce like a normal limiter should it just dropped the revs back a couple thousand...

Either way this problem has only just started, the counter has been fine the last 9 months.....Haven't ridden it 2day but i was on it for a couple hours yesterday and it was like it since start up...

AHHHHHHHHHHHHHHHHHH

That really is a very strange problem as the boss says normally a rev counter problem appears along with a flat battery but this isn't nesscessarilly a rev counter fault.
You say it's been fine up untill now I assume you mean that the rev limiter has cut in at the normal revs about 14.5 K or so ?

And now it seems to not do that ?

If so

I'd suggest that perhaps it's a fault in the ignition black box ?

[Jeppo]

By ignition black box do you mean the CDI?

Went for a ride today and its reading higher than ever, spent a fair bit of time reading 170000, and apparently ticking over around 8k...but the engine is running fine....Its quite annoying actually lol...Where does the rev counter read from?? I thought it was around the generator..but i don't know if thats right. What would you be having a look at to rectify the problem??

[RedexRobB]

It works from a lead off of one of the coils i think, it could be a dodgy connection, or even a dirty earth.

[Jeppo]

Had a quick look over and i just can't see anything obviously wrong...I'm just worried theres an electrical gremlin in there thats gonna cause me to break down at some point!!!

Any ideas on where to look and what to look for? I'm tempted to just take it to a garage, which is unlike me, i don't like other people working on my bike lol.

[masterofinsanity]

think i have a spare rev counter if you want to try it to eliminate yours?

[Jeppo]

Baz are you looking to sell me this rev counter? As i think it may be mine that is at fault...

I've measured voltages across the battery and it all seems normal, along with the smooth running of the engine, maybe its just the tacho that has had it? ..

[masterofinsanity]

i'll have a look tomoz for it its urs if it sorts your problem, if you wanna donate to the site its up to you?

[MillaMeter]

Hi,

Before you start spending money you might not have too, check the battery with a volt meter with the engine off, should read around the ~12.3v mark. Rev counters showing double is usally a sign of a fooked battery. Mine had this exact same problem once, I couldn't find the fault for love nor money but I got so miffed off 1 day I just twatted the rev counter with a rubber mallet and it now works a treat Turnt out to be corrosion/rust build up on the needle spring inside. Hitting it with a rubber mallet broke all the corrosion/rust up and freed the spring.

Regards

Rich

[Jeppo]

I've tested the battery and it's fine. I'll try a rubber mallet as i do suspect the spring...lol

[MillaMeter]

I've tested the battery and it's fine. I'll try a rubber mallet as i do suspect the spring...lol

Hi,

Ok, Just make sure not to hit it too hard as the face is glass. I twatted mine at the back of the rev counter if thats of any help.

Regards

Rich