Flat spot help

[dazer]

I bought my 1988 tzr from a friend about 3 months ago when his daddy bought him a saxo. it wasnt in very good condition but all the parts were there so i parted with my £350 and progressed from my kymco sector 125. because the fairings were not fited the electronic power valves were replaced with a lever, i din't really like the idea fo trying to open and close them all the time so during the rebuild i replaced them with the corect unit cables ect.. when the bike was finally finished it wouldnt start so the card was completely striped an rebuilt ( replacing the worn float valve needle) the tank was then cleaned and an inline fillther fitted.
i checked the float level using the correct method in the haynes maunal. and bingo it started first time. the probem im having now is as soon as i hit 4 and a half thousand revs it just coughs and spluters till six thousand revs. the plug looks fine and has been replaced the power valves are working corectly and the carb is spot on i carnt see any problems with the spark and im out of ideas.
now i can either change up at four and a half thousand revs resulting in a top speed of 40mph in 6th or i can strugle through the flat spot in 1st till i hit the power valves as soon as i do the bike will hit 100mph on the clock thanks to a un-named preformance can. any help would be greatly appreciated before i either loose my licence for accidently speeding or go insane sitting at 40mph.

[Tark]

Now that is strange? so up to 4 1/2 is ok then after 6 it is ok? No idea. Unless it is the ECU or powervalve contoller opening and closing the valve at the wrong times.

I cant help sorry. :roll:

[dazer]

thanks anyway. i was told it could have been a leak in the inlet manifold so i sealed the gasket before. havent had chance to test it due to the rain !!! but fingers crossed.
dazer

[Dan]

Let us know how you get on :)

[Spider]

i had that problem goes really groggy and flat at about! round 5 k yeah well move the needle on the carb up a notch to allow more fuel in it seemed to sort that for me ! but hell once the baby hits! the 6k she shure does fly dont she! well good luck let me know how u get on and wether my advice helps!

[dazer]

after yet another weekend im still not really any further. but if anyone could give me any advice on the power valve settings it would be apreciated. the reason is when i was fiting the cables i didnt have corect plastic weel (correct me if im wrong here) so i made my own metal one. but if the weel i made was a bigger diamiter than the standard one it wouldnt be turning enough. is it ment to turn 180 degrees from being open to being closed?. and am i right in saying the flat side should be flush when the power valves are open (when vied from the exaust port.) and when the power valve is closed the valve is moved 180 degrees. also if anyone can tell me the cable setup, is it 1-1 and 2-2 or 1-2 and 2-1. thanks.

[troutslayer]

firstly, its 1-1 and 2-2.

the valve doesn't move 180 degrees. its more like 90 degrees.
take the exhaust off and look upo the port. turn the ignition on. when it settles, the valve will be open, ie. flush with the port. when it is closed, it'll rotate and leave a 'step' in the exhaust port.

give taymars a call and get the correct part. no idea what its called, but explain it to him and he'll send u one, probably about a tenner. when u have that, stick it on. there is an aligning hole on it so u can set the valve up correctly.

[dazer]

thanks for the help. its definately the power valves. I think im missing a few other bits so im gona have a look around the breakers at the weekend.

[troutslayer]

as a temporary measure, set them to the open position, then disconnect the servo from the loom.

[dazer]

I went adound the srap yards today and managed to find one in southport that had a cylinder head including all the parts off the power valves. he also had the plastic disk for the end (left hand side) it only cost me 2 quid. but when i got home I discoverd it wouldnt fit. i think one of the parts iv got is of a tzr with a fixed powervalwe. the part im talking about is the part that is behind the shaped plate that holdes the cables. the only way i can get it to fit is if i remove this part but then im left with a gap around the actual pover valve( the part with the pins in it) is there meant to be a bush with a seal on it that fits in before the cable holder is fitted? id be quite suprised if anyone can make sense of me but if anyone can help. . . . .