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bike missfire at 5k
Posted: Sun Mar 06, 2011 8:01 am
by tz250racer
Hi,I have a 1991 Fzr1000 to use as a track bike only.The bike has a jet kit and a yoshimura exhaust.The bike starts and idle great but when I slowly increase the rpm and reach 5k the motor start to missfire and few pops are heard from the exhaust and won't rev higher.It's like the motor hits the rev limiter at 5k but I am not sure if it has one.Coils,Cdi perhaps.I would not think a jet kit would cause this problem.Any help would be appreciate.Thanks
Re: bike missfire at 5k
Posted: Sun Mar 06, 2011 10:28 am
by apsolus
some recient complaints just like yours ended up being the exup valve wasnt moving like it should. have you been through your carbs yet? might need a good inspection and cleaning
Re: bike missfire at 5k
Posted: Sun Mar 06, 2011 11:21 am
by rotortech
Hell yes a jet kit will cause this problem. If your mains are too lean it will just quit around 5k. If you are running the EXUP take the advice from apsolus and check it out.
Re: bike missfire at 5k
Posted: Sun Mar 06, 2011 12:40 pm
by tz250racer
Hi,the bike has a not working exup.The yoshimura exhaust won't take the exup,cables where missing but the exup motor is still bolted to the motor and to the cdi but nothing else is attached.Does the cdi have a rev limiter or not?.Carbs where all cleaned.Thanks
Re: bike missfire at 5k
Posted: Sun Mar 06, 2011 5:18 pm
by sweekster
Have to agree with what both have just suggested here. My 1000 did the same thing and turned out I had a couple clogged main jets. Would not hurt to give the jets a good cleaning along with servicing the exup valve if you still have that header on the bike
Re: bike missfire at 5k
Posted: Sun Mar 06, 2011 5:37 pm
by tz250racer
The bike has a full yoshi exhaust and not the stock header.
Re: bike missfire at 5k
Posted: Sat Apr 02, 2011 10:21 am
by Ice Queen
Almost certainly Exup motor related. Someone on the exup forum posted a thread showing a circuit board he had made up to "fool" the CDI unit into thinking that motor was still attached
Re: bike missfire at 5k
Posted: Sat Apr 02, 2011 10:24 am
by reelrazor
Hey, you 1k geeks out there?
Could this be a low fuel switch issue?
Re: bike missfire at 5k
Posted: Sat Apr 02, 2011 4:19 pm
by yamaha_george
Ice Queen wrote:Almost certainly Exup motor related. Someone on the exup forum posted a thread showing a circuit board he had made up to "fool" the CDI unit into thinking that motor was still attached
IQ,
do you have a link for that "trick board "? would be useful to have it in the
wiki
Re: bike missfire at 5k
Posted: Sat Apr 02, 2011 5:50 pm
by DonTZ125
http://www.exupworldwide.com/forum/view ... eliminator
Note that I have NOT checked these. Blowing up your TCI chip is at your own risk
I think you have to be registered & logged in to view it; here's the circuit for those somewhat interested. (I'm considering offering this as one of my products - yes, I'm going to be launching ANY DAY NOW
)
The wires are I believe for a
('94 YZF750)'06 R6V; oddly, they do not match the manual I have for a '95 YZF750. Comparing manuals, the '95 YZF and all FZR1000s have the same EXUP wiring. Looking at the manuals, and comparing the graphic, I'm going to say the following is probably right: (graphic = YZF750 or any FZR1k)
B/R = B/R
B/G = B/Y
W/R = W/R
B/L = Y/L
L = W/B
TZ250racer - when you say the bike has a 'not working EXUP', do you mean the servo doesn't work, even though it isn't plugged in? If the servo works & is plugged in, even if the cables & valves aren't there the TCI will still be happy.
Edit - more digging, and I've found the bike these wires are for - a 2006 R6V.
Re: bike missfire at 5k
Posted: Sun Apr 03, 2011 3:00 am
by Ice Queen
DonTZ125
Pretty sure that servo motor wiring for R and RU models are different. will have to spend bit more time looking.
Re: bike missfire at 5k
Posted: Sun Apr 03, 2011 3:13 am
by DonTZ125
IQ - Dense moment here; the only 'RU' model I can think of is the FZR750, which was non-EXUP. Clarify?
Also, I'm looking at the service manuals for the FZR1000W (including A, B, & F), and the YZF750RE; their EXUP wiring all match what I've suggested above.
Re: bike missfire at 5k
Posted: Sun Apr 03, 2011 3:19 am
by Ice Queen
The RU model is 1000 1991 onwards.
Just had a look at wiring diagrams and
I THINK wiring is as follows:
R model 89-90 B/R; B/Y; W/B; W/R; Y/L
RU model 1991 onwards R/B; R/W; B/Y; W/B; Y/B
clear as mud isn't it
!!!!!!!!!!!!!
Re: bike missfire at 5k
Posted: Sun Apr 03, 2011 3:33 am
by DonTZ125
Sitting here with the FZR1000W ('89) manual open in front of me, which also includes the B ('91) and F ('94) wiring diagrams. I also have the YZF750RE ('93) in front of me. All show my colours.
I think that comes under the heading of 'caveat emptor', and "everything about these silly things is different!"
Re: bike missfire at 5k
Posted: Sun Apr 03, 2011 6:30 am
by yamaha_george
DonTZ125 wrote: Sitting here with the FZR1000W ('89) manual open in front of me, which also includes the B ('91) and F ('94) wiring diagrams. I also have the YZF750RE ('93) in front of me. All show my colours.
I think that comes under the heading of 'caveat emptor', and "everything about these silly things is different!"
Where the heck is SWEEKSTER when you need him to do the FZR historian bit .......................................