High load miss at >7500rpm

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Gidanski
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Posts: 60
Joined: Tue Oct 30, 2012 10:53 am
Bike owned: 1994 CB400SF, 2008 CBR600RR
Location: Australia

High load miss at >7500rpm

Post by Gidanski » Wed Jan 08, 2014 10:46 am

MY superfour has developed a weird problem since I have got it back on the road and I cant seem to figure it out. It pulls fine from 2500rpm at full throttle but as soon as you hit 7500 it just seems to stop dead. No idea whats going on.

Mods that have been done to it are as follows:
Danmoto Slip on and link pipe
105 Main jets (Too small still maybe?)
K&N Air filter
2.5 Turn Idle mixes
CDI Derestrict Resistor
CR9EH Spark plugs (One range colder)
16/37 Sprockets

Have put new plugs in it today and the problem still persists. It also has new lead ends and the problem only occurs when trying to access the higher part of the rev range at high throttle. Haven't tried lower throttle as If I am up in that part of the rev range then I will more then likely be using over 3/4 throttle anyway.

Any help would be greatly appreciated.

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hannakournikova
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Bike owned: NC30, NC35 & SP2
Location: Belfast, Northern Ireland

Re: High load miss at >7500rpm

Post by hannakournikova » Wed Jan 08, 2014 8:50 pm

Gidanski wrote:MY superfour has developed a weird problem since I have got it back on the road and I cant seem to figure it out. It pulls fine from 2500rpm at full throttle but as soon as you hit 7500 it just seems to stop dead. No idea whats going on.

Mods that have been done to it are as follows:
Danmoto Slip on and link pipe
105 Main jets (Too small still maybe?)
K&N Air filter
2.5 Turn Idle mixes
CDI Derestrict Resistor
CR9EH Spark plugs (One range colder)
16/37 Sprockets

Have put new plugs in it today and the problem still persists. It also has new lead ends and the problem only occurs when trying to access the higher part of the rev range at high throttle. Haven't tried lower throttle as If I am up in that part of the rev range then I will more then likely be using over 3/4 throttle anyway.

Any help would be greatly appreciated.
what have you changed prior too of going back on the road?

Gidanski
Settled in member
Posts: 60
Joined: Tue Oct 30, 2012 10:53 am
Bike owned: 1994 CB400SF, 2008 CBR600RR
Location: Australia

Re: High load miss at >7500rpm

Post by Gidanski » Thu Jan 09, 2014 1:43 am

The only other thing that has been changed is the instrument cluster. Replaced with an Ebay one as the old one was smashed up. New one did not appear to have a speed sensor or resistor, hence the Derestricter mod.

Gidanski
Settled in member
Posts: 60
Joined: Tue Oct 30, 2012 10:53 am
Bike owned: 1994 CB400SF, 2008 CBR600RR
Location: Australia

Re: High load miss at >7500rpm

Post by Gidanski » Wed Jan 15, 2014 8:51 am

Got it all sorted, turned out to be a bad earth between the battery and chassis.

Bigdave982
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Location: Cambridge

Re: High load miss at >7500rpm

Post by Bigdave982 » Fri Mar 07, 2014 3:06 am

Hi

Just thinking out loud here...
Have you checked the rectifier?
Have a look at the coil pickups, there's 3 on the generator casing

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