South West Bikers | Motorcycle Forum

This is pi55ing me off now.
When I got the bike all worked fine, reved up to the red, then it started to get lumpy/flat spots so Paul kindly adjusted the float heights and the bike runs smooth........ Right up until 10k revs, then it will not go, in any gear.
No go after 10k
Paul has suggested a dynojet kit but I wondered if there was any other explaination - And why would a dynojet kit make that much of a difference.
The bike has only done 26k (kms)

have you got a kink in a breather pipe or something similair
who is paul,is he a trained mechanic, if you want a decent mechanic to look at it pop up to JP Motorworx on the way to luxulyan and he'll sort it for you

i know Paul quite well he's a fully trained mechanic 3 years at college passed all courses with distinctions or merits, time served in various garages inc an engine rebuilders in launceston, runs his own part time bussiness, i know this coz its me
the zzr carbs aren't the best especially if your running a 4 into 1 they tend to have a few flat spots, as the carbs have worn they tend to over fuel and when the bike hasn't got an air filter that doesn't help matters, ive found a few jets m8 if you want to pop over i'll take another look for you, i could get it better but really needs the filter and a run on a dyno to find out exactly whats going on through the rev range
i even worked on a 10,000 mile zzr d once and even then the diaphrams were really thin and that was causing the over fueling that made it run like a sack off poo poo

OK mate yeah I'll pop over again... Weekend good for you?
You done a grand job, bike runs so much better now, and handles better too; so much quicker into corners I had forgotten about the filter to be honest oops! Maybe get a K&N - Where's best place to get one of them?
But the no go after 10k is such a pain, takes away so much speed and power, like its being restricted...

Local dealers should be able to order you one in or try ebay...

Cheers all, I'm off to scour the bay for a filter and get some new spark plugs

Best bet is to stick an OE filter back in and go from there. Running with no filter can have a huge impact on a bikes performance (in both the long and the short term). K&N's carry a name as legacy, rather than fact, in many cases now. As with many things, they came in at a time when the engine designers weren't necessarily right on top of their game, and as a result air-box's were quite restrictive, so there were big gains to be had by ditching them. Nowadays that isn't the case and OE filter & airbox design is pretty good. At best you might see an odd BHP or two difference and yet filtering may be nowhere near as good - there have been some very interesting tests done on filters in the states, with some surprising results.

With no filter fitted the fueling will run lean this is likely to be why you cannot get the bike to rev out fully. The ZZR carbs can be finicky especially as over time the emulsion tubes wear oval which stops them metering the fuel correctly on needle, although this usually manifests itself lower down the rev range between 3.5k and 5.0k rpm. A dynojet kit will come with new needles and jets and sometimes new emulsion tubes, as well as sometimes air correctors and slide springs etc depending on the model. Most of the Keihin CVKD carbs require a restrictor in the main airjet with jet kits otherwise they will not run well.
Fit a new filter which should then allow the bike to rev out. If you still have problems then you will need to get the bike on a dyno and have it set up properly. I supply both K&N filters and Dynojet kits for less than most places, as well as setting them up on my dyno. If you want a price on a K&N or a Dynojet kit and or set up then let me know.

Ok Cheers fellas... I didn't manage to get filter or plugs today but will go with a standard filter, apprently K&N dont make one for the D model anyway...?

they do m8 as i've got one, but they didn't make alot apparently but you can get a fireblade one to fit

I dig your attitude Paul - If I wont fit - MAKE IT FIT! Haha winner

meganall wrote:they do m8 as i've got one, but they didn't make alot apparently but you can get a fireblade one to fit

they dont list one in the K&N catalogue ive got, if they made some it wasnt very many as you say

the k and n for the d model is rarer than rocking horse poo