need help with 93 tiger 900 electrical problem

[bull]

bought this 93 tiger 900 some 6 months ago. It had been parked up for 5 years because of an electrical problem. I am pretty good with motorbike electrics, but i can't solve this problem so i need your help. First the rev-counter does not work when the bikes lights are off, but will work when they are on, but only up to 3000rpm when the battery volts goes over 14.4 volts the rev-counter stops working and falls back down to zero. the bike will also sometimes drop in and out of one of the cylinders. Now here is the real mystery, if i unplug the alternator everything works fine including the rev-counter. so i checked the alternator and the rectifier/regulator and they worked fine and the battery is also charging perfect. but to be sure the it was not the alternator i left it unpluged and hooked up a battery booster to the battery and as soon as i did the rev-counter stopped working and had same problem with the cylinder again. I then dropped tested all the wiring loom looking for a ghost, but could not find any problem. finally i left it into the shop and after 20 hours working on it and at great cost to myself they could not find the problem either. Now i am not stuck as i have other bikes, but i will have to sell it for parts if i can't find the problem. If anyone has had this problem before i would be very grateful if they could tell me what it is.

UPDATE: i changed the battery and it was not the problem. When i was checking all the systems i found something new, when i switch on the hazard lights the rev-counter goes up and down at the same rythem of the hazard lights, let me know if any of you think of anything

[Gripper1974]

Never had a problem like this myself but it might sound daft but could it not just be the battery discharging to much power and overloading the system.

[bull]

THANKS Gripper1974, not so daft at all and it could be the problem, i will put another battery into it and see will it solve the problem.

[tony23]

Bull, you have done everything I would have done mate, and to be honest I cant think of a single thing that would do that...The only thing I would be suspect on is the R/R..but like you say it has been checked,
You say 20 hrs in a shop,are you happy with them to charge and not even have any ideas?
Good luck,

[tony23]

The only thing left to do is try one thing at a time..
The fact that the rev counter wont work without the lights say to me a bad earth/feed.
But I dont know the system it works on.
I know this sounds stupid but have you checked the bottom of the fuse block ?

Im thinking the lights switch feed line is shorting the feed to the rev counter.
How about taking the headlight lamp out to kill the return to negative and see if the rev counter works then.
I tell ya what, this problem's a good un..
Im gonna have a little think

[tony23]

Looking back at your post ....

the R/R allows the voltage to exceed 14.4 ??
How old is the battery?
There is a very definite possibility of overcharging.
What voltage is the alternator producing at revs ?

[tony23]

Can you source another alternator? Another battery might help..Im leaning to the R/R..
The misfire, ..
Thinking about it, double check your R/R, can you borrow another R/R just to check the charging system...

Have you asked on any other sites for help ?

[bull]

thanks tony23, yes i did remove the fuse box and check it, it was fine, i also ran a direct feed from the battery to the rev-counter and it had no change, i also ran an earth wire from the earth on the rev-counter to the bike frame and engine and with no change. i also checked all the wires for grounding but could not find a thing, i even pulled the fuse for the lights and with no change. one of the wires going to the rev-counter is running to the cdi but i can't see it being a problem with the cdi as it works fine when the alternator is unpluged. the other wire runs to one of the coils, so i tested the coil and it was fine,but to be sure i changed the coil around, but no change. thanks for the help tony. it is a mystery.

[bull]

thanks tony, in the shop they removed the alternator and had it checked, they also installed new R/R just to add to the cost, but no change.

[Redmurty]

My 06 Tiger died this weekend I think its the RR. I have been reading the www.Tigertriple.com post up on there and see what the guys say cheers Spud