Hey,
I am having an absolute nytmare! i brought a gk71f gsxr 400 single headlight which is an 86 E reg. i have had a full service and it passed its mot straight away which cost 300quid all in. as soon as i picked the bike up it wouldn,t idle, ran like crap and wouldnt rev passed 7000rpm as it sounded like it was hitting rev limiter. on this i took it to the bike shop where i had the carbs ultasonic cleaned and loads of crap were found in them, new o rings, and jets cleaned etc etc. as i turned up it was being rolling roaded and it still hits 7000 revs and does no more othr than sound like its bouncing off the rev limiter. is this the cdi? my cdi has no numbers on it so im stuffed and dont no what to do. any help would be appreciated i am at an absolute brick wall. Thanks

have you got any printouts?
Is the bike standard?

hi there,
I dont have a print out as he stopped the dyno and just said thats not good it shouldnt be doing that? was like great. It is totally standard in every way. From what was done of the rolling road the air fuel mix was good as it wasnt straying to far from the horizontal dotted line of 'perfect' air/fuel mix, went a bit lean briefly but was nothing, all four cylinders were firing as they should, the highest bhp was 29bhp amd the power curve was on its way up until around the 7000rpm limit and then it would jus rev limit (or sound as if).basically from what i can gather up until that rev renge in every gear it runs perfectly as it should. I hope this has made sense. can you refurb exisiting cdi's? any help is greatly appreciated. Thanks

i wouldn't suspect the cdi initially.
there are a number of things it could be.
coils
pickup
main jet issue
etc etc

if it was electrical it would have been showing signs of it being rich as it cut.
without hearing the bike or seeing the printout i can't say too much more.

Okay cool. I think I have found a cdi for little money so as bike is still at shop ill put that on and get it rollin roaded and if its not fixed ill get the printout and have to go from there with your suggestions working through each one. It's devastating, is this something that could become costly as have spent a small fortune alreasy. Thanks

Are you 100% this bike dont have a 33bhp restriction fitted.

haha theres a point!

Hey chris hows things?

hey.
lol i dont have a clue? if it was that i would feel pretty embarrased but the joy factor would make me get over it rapidly! Where would this restrictor (s) be likely to be located? the guy i brought it off said it was crazy fast so i never thought of this.
Thanks guys

I would'nt think its 33bhp but seems to run like one. would be washers in the inlet tracks or washers under the carb tops to stop the slides opening up fully.
The 71F has two carbs with twin slides and ive seen them not fully open if the slide diaphragm is knacked.
sorry to jump ya post-Hi Daz- things are good, PM sent.

okay cool thanks for this help. Ill have a look this week and let you guys no. All being well should have a working bike sometime soon. Is it difficult to load pics on here as ill get some uploaded and document the restoration etc. cheers