engine missfire at 4.500rpm and over

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tilly
Cucciolo - the Lil Pup
Posts: 7
Joined: Tue Dec 14, 2010 12:51 pm
Location: england

engine missfire at 4.500rpm and over

Post by tilly »

seem to have a missfire at just over 4.500rpm,cleaned carbs 40mm
still missfiring, any ideas would be welcome.
Its a 900sd by the way.
Thanks Tilly

rwhc80
750 GT
Posts: 174
Joined: Sat May 16, 2009 7:19 am
Location: Melbourne Australia

Post by rwhc80 »

G'day Tilly,

I would be more inclined to check your electrical/spark system first. Check the condition of your plugs, as this is a good indicator of what's going on. I.E what color are they burning ? Perhaps even a simple spark test to see if you have a good strong pulse.
Also, does the bike have the original bosch coils ect ? and have your pickups been rewired at any stage ? ......both common faults !

Good luck with it, cause the SD is a brilliant all round bike to own.

Cheers
Rick
I have desmo disease, I just hope they never find a cure !!!

tilly
Cucciolo - the Lil Pup
Posts: 7
Joined: Tue Dec 14, 2010 12:51 pm
Location: england

miss fire

Post by tilly »

I seem to have found the problem as there seems to be water geting into the l/h crankcase were the pickups are.
Will strip it down and let you all know.

rwhc80
750 GT
Posts: 174
Joined: Sat May 16, 2009 7:19 am
Location: Melbourne Australia

Post by rwhc80 »

Tilly,

A little unusual for water to be the problem, but I guess anything is possible. Just check your wiring to the pickups as these tend to break down over time and cause problems. In fact, I would re-do the wiring whilst you have the thing in bits, if it hasn't already been done, cause it will surely cause you problems down the track, even if it isn't the issue right now. ????

Just remember, the position of those pickups is critical, if you move them you will need the factory tool to reset.

All the best
Rick
I have desmo disease, I just hope they never find a cure !!!

tilly
Cucciolo - the Lil Pup
Posts: 7
Joined: Tue Dec 14, 2010 12:51 pm
Location: england

Post by tilly »

Many thanks Rick for the info, the wireing looks to have been looked at as the wires are connected by horrible spade connectors,going to try plugs without ressistors as it seems to have started when I changed plugs, just a thought.
Again many thanks Rick ;)

User avatar
Craig in France
Cagiva Gran Canyon
Posts: 881
Joined: Tue Mar 23, 2004 3:58 pm
Location: Montpellier, France

Post by Craig in France »

tilly wrote: ... going to try plugs without resistors as it seems to have started when I changed plugs ...
Hi Tilly,

No resistor plugs with Bevels. Just use NGK B6HS.

Ciao

Craig

tilly
Cucciolo - the Lil Pup
Posts: 7
Joined: Tue Dec 14, 2010 12:51 pm
Location: england

Post by tilly »

Horray she's a runner,bloody resistor plugs, what a load of shite.
thanks to all who posted replies :P

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