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Mikuni Needles and Jets Wanted
Posted: Thu May 08, 2008 4:53 am
Author: SP10mk11
Hello
In my long quest to get my 1978 Z1R running right, I have come to the conclusion that the needles and needle jets are worn
I tried to get some from Zpower but they say they are no longer available
The numbers are:
Needle 5CN15
Needle jet 258 0-1
I have treid various mikuni spares suppliers (thanks a lot to Steve Doran of motocarb) but they have all said these are OEM parts, so I am thinking i am stuffed on this one
Has anyone any ideas on how i could get round this
Thanks
Gary
carb
Posted: Thu May 08, 2008 7:29 am
Author: AL MARSHALL
hi give these a try
www.nrp-carbs.com 01618328646 in manchester
they have always had the carb parts i have needed regards al
Posted: Thu May 08, 2008 10:03 am
Author: Z1RII
the needle 5CN15 is no longer available, even not from mikuni.
you can replace them with 5DL31 from the earlier carbs. they have the most same performance of the 5CN15
the needle jet is still available from mikuni
you can get the parts from mikuni-topham in germany
Posted: Thu May 08, 2008 5:40 pm
Author: Pigford
Mikuni Needles and Jets Wanted
Posted: Thu May 08, 2008 6:55 pm
Author: SP10mk11
Right thanks to you all for your comments and suggestions
I will try the companies mentioned tomorrow
I did think about using the 5DL3 needle, but i would also want the matching needle jet, and without any i cannot get the series number i would need, any ideas on this?
Thanks
Gary
carb
Posted: Thu May 08, 2008 6:58 pm
Author: AL MARSHALL
talk to the companies.they will know what you want,let them do the work

they are the experts
mikuni needles and jets wanted
Posted: Fri May 09, 2008 9:44 am
Author: noelmcguinnessz900
hi gary try k. williams motorcycles 01872 560003 not too far from you near truro
Mikuni Needles and Jets Wanted
Posted: Fri May 09, 2008 11:20 am
Author: SP10mk11
Hello AL
Thanks for recommending NRP, i bought 4 Keyster complete carb kits for £63.50 for the Z1R so they will have the correct needles and needle jets etc.
I nearly bought some from a guy a in Germany at a higher price becuase i coudnt get through to NRP (thanks christ i went out for an hour) and got through when i got back.
I will let you know how i get on with these kits
Thanks again
Gary
Mikuni Needles and Jets Wanted
Posted: Mon May 12, 2008 8:12 pm
Author: SP10mk11
Got the kits safe and sound

, fitted them no problems

, ran the bike and then balanced the carbs

, this has almost cured the original fault

, the bike revs and pulls much better though
I am stumped as to why now i still have this minute stutter at pull away, no where near as bad as it was though
one thing with the kit is they supply a 105 main jet where as the Z1R uses a 107.5 which is what i put in, surely this correct.......

or do i have to fit the 105 main jets
Yours a bit frustrated
Gary
Mikuni Needles and Jets Wanted
Posted: Tue May 13, 2008 10:01 am
Author: SP10mk11
Just a thought ! should there be a spacer between the needle "E" clip and the plate that screws down onto it.
Only i have noticed that the needles will move up and down a couple of mil when assembled
Hmm im wondering if this is causing the off idel misfire
Mikuni Needles and Jets Wanted
Posted: Tue May 13, 2008 12:58 pm
Author: SP10mk11
Latest update
I downsized the main jets to 105's (as supplied in the Keyster kit)
I put an extra "E" clip above the mormal one and this has stopped the needles moving up and down in the slides now, re-balanced carbs)
Result, much smoother and cleaner running and pulls better at all speeds, brought back the power surge at about 6000 rpm (rev counter a bit wobbly)
Off idle stutter all but gone, far easier to pull away without the bike lurching around now........
But what do i look at now? down sizing the pilot, this running rich at low rpm has always been a problem, changing the needles and needle jets plus what i have now done has improved the situation.........but christ knows wheree i go now
Any ideas?
Thanks
Gary
Posted: Wed May 14, 2008 9:42 am
Author: Z1RII
i tried to use the keyster junk one time years ago and have thrown them direct to the rubbish.
same problems as you mentioned, needle has to set down and all this stuff.
i´m running the 5DL31 with O-1 on all my Z1R´s and MKII´s with no problems, no after jetting, nothing. and they costs not as much as the keyster junk.
steven topham in germany has all the mikuni stuff you need for much less prices as kawa wants for the parts.
roll on!
Mikuni Needles and Jets Wanted
Posted: Wed May 14, 2008 9:52 am
Author: SP10mk11
ARGHHHHHHHHH dont tell me i have bought a load of shite please
My needle jets were worn a lot compared to the new needles and jets, and changing all this has improved the running and to some extent the off idle stutter
I do have an old set of 26mm carbs with 5DL3 needles in them, i am just so sick of taking the carbs off (henry the universal adjuster nearly came out a few times

)
But i do thank you for responding
Gary
Posted: Wed May 14, 2008 10:17 am
Author: Z1RII
they are not shit for people who want the bike running in any way, but for me it is junk. i do need full power and good engine performance, and, to safe some gold nuggets coming into the gas tank.
your float high is correct?
Mikuni Needles and Jets Wanted
Posted: Wed May 14, 2008 10:40 am
Author: SP10mk11
Ok thats is fair comment, thanks
Yes i have even tried setting the float height so there is a lower fuel level in them
Regards
Gary