high rev problems!

[steve87]

hi people. i am new to the world of the zxr400.
have a bit of bike knowledge and can pretty much strip and rebuild the zxr now.
i have just bought a zxr h1 model, qand its brilliant. the o nly problem it has is that it has a 11000 rev limit to it when riding. this fluctuates slightly depending on the gear, but as a whole, stopps being able o rev at 11000.
when not in gear, will rev up to the 14000 mark, so i would suggest its a fueling problem, not cdi unit.
i have not changed the fuel filter yet, but im guessing this needs changing as it looks pretty damn dirty atm.
i have stuck a load of fuel system cleaner through the petrol and apart from the 11000rpm limit, rides and responds dead nice.
i am putting a new clutch and springs in, as the old one is slipping slightly.
im thinking it will either be a slightly blocked jet or the fuel filters.
is there anything else that it could be?
i plan to do the fuel filter tomorrow so we will have to wait and see.

steve

[RedexRobB]

Sincs its an H1 it will be an import and will have a speed restrcitor built into it. This kicks in at around 10K rpm in top gear, so it could be this. Check to see if its got a derestrictor box by looking round the back of the clocks, if the speedo is plugged into the loom then its speed restricted.

[steve87]

it has got a mph clock put on it rather than the speedo, and has a random plug hanging out the back, so im guessing that the restrictor has been removed. im pretty sure its fuelling, but i will check, and its in all gear

[RedexRobB]

Im not 100% sure on this but i believe that when the clocks arent plugged into the loom on imports, a default 10K rpm limit kicks in from the CDI, so this could very well be your problem. You can buy a UK CDi or derestrictor to sort it Alternatively fit back on another kmh speedo (uk clocks dont have the speed restrictor circuit) and pick off the tag tag inside which will de restrict it

[steve87]

ok....
i will go through everything i have done and see what you think
i bought the bike a week ago.
the bike has been sat for at least a year, but i now have it up and fully running.
it starts on the dot every time from cold, and most of the time from hot,
so i am pleased with that.
i have put a new fuel filter in, new spark plugs oil etc.
i have order a new clutch ( went for the ecb heavy duty plates and springs).
when i took the old plugs out, they were very black and wet, i checked the mixture which was running at about 6 screws out!!!!
I have changed this to 2 and 1/4 turns out, like the manual says.
i have ran some fuel system flush through, which has made the bike run sweet.
today i fitted the new fuel filter and it seems to run a little better.
now my next few quandries.
every so often, the bike will stall at junctions when slowing down.
i personnally think this is because it needs a new clutch and springs, and the clutch isn't releasing properly.
it also seems that it is still running slightly rich, but the carbs are set at what the manual says.
it has had a mph speedo put on. this works fine and acurately, except there apears to be an extra plug floating round at the back ( but i guess this was for the old kph speedo)
My thoughts are, the main jets are still blocked, because in the first few gears, it will rev to about 12, with clutch in, it will freely rev up to about 15. In top two gears will rev to 11, but if you cruise at this, it judders forwards, as if more fuel is trying to get in.
this leads me to the conclusion that this is the dirty jets.
would you agree?
my thoughts are if it were the cdi, it would rev fine in the first few gears, and be limited in top gear, for the 112mph?
everything else on the bike is spot on.
the next question, how much for a new set of jets?
where do you order them from.
i have an after market end can, so should i go up one size, or stick with standard ( 98 i believe that is)

please help!!!!

i will stick some pictures on of the bike in question


steve

[RedexRobB]

starting to sound like a fuelling problem isnt it.

Zimm is the man to ask or Rover220, they are pretty experienced with all that fueling malarky and jets n stuff.

What did you use for the fuel flush? As always i reccomend a shot of Redex in the tank and run that through.

As for stalling at junctions make sure the clutch cable is set properly, should be about 5mm of travel at the lever before the slack is taken up and starts to disengage the clutch.

[rover220]

where are in the country are you?

[steve87]

rugby, near coventry in the west midlands.
i will slap a load of redex through today, see if it helps.
steve

[RedexRobB]

Buy the little bottle of redex if you can, just a shot of that in the tank, and see how it goes. Its only a qid or so saves forking out for a larger one.

[rover220]

i have a spare uk cdi you can try if you want. it will rule out the unplugged clocks theory which seems likely at this point.

[steve87]

please please please please please.
how much do u wt.
mine is a h1, will the l shape fit.
i would really appreciate that.
give me a call on 07764500439 if needs be.
steve

ps i have used the redex, most prob a little much. bike still runs slightly rich i think as it never needs any choke? even when cold.
i am gonna turn e mixture down to 1.5 turns out, from the 2.25 the manual says.
i think this will help big time.
then the last thing is the cdi, so i could do with that asap,
steve

[zimm]

your bike is restricted mate, the spare plug normally plugs into the kph speedo, which contains the restrictor circuitry, this circuit limits the bike to 180kph by sensing where the needle is pointing, if you remove unplug the speedo to "by-pass" the circuit (as has been done on yours by fitting the uk spec speedo, which doesnt contain the restrictor, hence the spare plug) the CDI goes into "limp home" mode, limiting you to around 10,000rpm .. you need to do one of the following,

1) fit a kph clock and live with 180kph (112mph) top speed

2) fit a kph clock, and one of those kph-mph converter things .. no way your bike will do 180mph, so the restrictor doesnt cut in

3) fit an Mmax box (connects to the "spare plug" and tells white lies to the CDI)

4) fit a uk spec CDI (doesn't have the restrction circuit, so will work with any speedo), this also raises the rev-limit to 14,900 instead of 14,500.. but may need a different ignition rotor to make it work as it will be off an L model and yours is an early H1.

you need to get this sorted first and then deal with the other running problems or you wont have a reliable base-line to work from.

it will seem to go to 11/12/whatever rpm, but thats just the clock error/momentum ganging up to confuse you, not to mention static etc getting straight to the cdi through disconnected plug by the clocks.

your end-can wont really affect the main jet size as the link pipe is baffled anyway

I generally set mixture at 2.5 ish turns out, it doesn't change things that much tbh, and is the last thing on your list to be sorted (but yeh, 6 turns out is way wrong .. lol.. ) if too lean the revs will "hang" at around 2k before settling, you want to be just a tad richer than that.

for new jets give cradely kawasaki a ring, (or anywhere that dyno's bikes, they'll have buckets of them kicking around) also pay attention to the float heights and the float valves ability to seal properly as if the levels's too high/low it can play havoc with the midrange "feel" of the bike. whilst in there give the pilot jets and emulsion tubes a thorough examination as these will clog with mank before the mains will anyway, and can cause many random fuelling symptoms.

hope this is some help.

[steve87]

i have sorted a uk cdi out with rover, so trying this on thursday, hopefully will all fire up nicely, if not, gonna do the kmph into mph swap, then put the mph face back on,
wicked

[zimm]

gonna do the kmph into mph swap, then put the mph face back on,
wicked

the scales are different