Phone a friend

Can anyone help my mate Dave? I've just had an email from him about a problem he's experiencing with his Hairnet.

'Lets start at the beggining. I have a hornet 600 (2000) jap import which i unfortunatly had a lowside on (very minor) which needed a new fork, clock, headlight and fender. Before the accident the bike was running perfectly and had just had new plugs, oil filter and air filter.
I had the bike out yesterday for the first time since and when the bike reaches approx 4,500 rpm the engine looses a lot of power and sounds like it's hitting an imaginary rev limiter although you can increase the revs with this strange noise. You are unable to get past this noise in a high gear as the bike doesn't seem to have the power.
The carbs have been stripped and cleaned and with the airbox off and running the problem does not go away when squirting wd40 down each of the carbs. Tried different plugs and tested the coils.
It seems like an electrical problem and not a fueling issue.'

I've heard it and it sounds like it's misfiring at higher revs - but the plugs, leads and coils have all checked out OK. The only thing electrical damaged in the accident was the clocks, and I'm not sure how they can be at fault. Below 4.5K the bike runs perfectly.

Any ideas, anybody?

Carbs... so I'd suspect HT leads? If it's electical something is playing with the timing in the pulses to the plugs.

Not knowing carbed bikes in general, I dunno. On an FI system there's probably half a dozen sensors I could name, but I don't think that many of them apply here.

HTH

Originally Posted by Baph

Carbs... so I'd suspect HT leads? If it's electical something is playing with the timing in the pulses to the plugs.

Not knowing carbed bikes in general, I dunno. On an FI system there's probably half a dozen sensors I could name, but I don't think that many of them apply here.

HTH

It's had new HT leads, replaced one at a time and tested in between. It's had the carbs stripped, cleaned and jets all blown through with HP airline.

I initially suggested a coil breaking down, ht lead or plug cap tracking, but all have been replaced or tested against known good stuff.

Sounds like the timing is out.

Originally Posted by Swiss

Sounds like the timing is out.

Hmm, now that was one of my first thoughts, but I don't know if he's already tried that... I shall ask.