Bollo**s I think I've done it now!!!!

[Mark Stratton]

I was thinking of suggesting that Mrs S goes with them as a maid / nanny or sumink. At least I'd be able to get on with the rest of the rebuild without getting ear ache.

[RALPHARAMA]

Women are great, providing you remember the two golden rules
1) Don't marry 'em
2) Don't make 'em pregnant

There are plenty of other guidelines, but trangressions of the others can always be sorted, but breaking the two cardinal rules can prove terminal

[Al]

This is what you get for about £40 if i remember.
Takes about twenty minutes and fries the motor but fun to watch.
Mine smoked so much it set off the smoke alarms several times and i had to disconnect it for them
The most important bit is the lower down graph.
That is the one that tells you what the fueling is about.
Below the dashed line is rich i believe and above the line is weak mix.
Ideal is 14.7:1 but this shows it as 13:1
i.e mine was very rich at the bottom end and progressively weaker in the higher reaches.
The two different coloured lines are explained below and you may notice that as the blue line stops and starts it co-responds to the change in gears. Cant tell you why it goes very weak when you shut the throttle i would have imagined that that would send it off the low end of the rich scale but apparently not.


Top graph is (red line) wind it up in top gear from no MPH
(blue lines) are second third fourth and fifth gear respectively from zero revs with change in gear at the top of the peak of power developed in that particular gear.

Peak horse power is achieved in third gear curiously at 85 and successive gears only make you go faster but with slightly less horse in each.

Its a harsh thing to do to an engine but not as harsh as the next five thousand or so miles i gave it.




AL

[Taffus]

Al are those guys you used geared up to do jetting ie they hold stock of jets?

[Mark Stratton]

Al

thanks for that, it is obviously the way to go. The boys at Doubletake Motorcycles in Southampton are also listed on the same website and these guys are within pushing distance of me however I've done enough pushing lately so I think I'll wait untill its running!!!!!
Obviously this graph shows you what is happening throughout the rev range however are they then in a position to offer advice on the correct jet sizes, needle settings etc to give optimum performance?
Hopefully if I can get a chance to speak to Steve at Debben's he will be able to assist with some suggestions.
From the suggestions that have come in so far it would appear that the ignition is the culprit, oh and my overeager right hand!!!

Anyway feeling a little more positive that the Z is not completely scrap now following comments from Pigford so its onwards and upwards.
Still looks like the ZX10 nail might weeze its way to the Ace though.

[BShaw]

Mark, Mke sure your ignition is spot on then get it set up on a dyno you will spend ages mucking about otherwise only use Premium grade petrol (97) it will still pink (you now have a higher compression ratio) but you will learn to change down before opening the throttle. Zorded is pointing you in the right direction.
Baza

[Al]

Gents; (Reading Branch, Bramley) they told me that they keep stocks of jets for all the major carb manufacturers.

They do this for a living and do it all day every day.
Based on the £40 assessment that you see above they can tell exactly which jet needs to be changed, which parameters need to be altered and which settings need to be adjusted.

I would anticipate that they would get it right first time and i believe they offered me this service based on a £35 per hour charge rate or thereabouts to re-set and re-jet.

They change the jets required whilst the bike is sat on the dyno and run it up again afterwards and give you a new graph showing the new settings and new ratio / power output.

I didnt have mine re-set because i was about to have it bored oversize, i only had it done because my friend paid for it after he had his done and was super impressed.

I dont know how you value your time but i spent the next few months trying to get mine right before it was bored out. They do it in half an hour or so and you only pay for the jets you end up with!

VFM i believe.

They also sell and fit power commanders / dyno jet kits, and tuning bits / tyres etc etc.

May also be worth mentioning that they have bust times of year when you need to book a month in advance!!


Hope this helps.



AL

[Mark Stratton]

Thanks Al

Will definitly pay them or the guys at Doubletake Motorcycles a visit when I have it all back together and running half decent.
Seems like money well spent to me! If I did this to start with then I don't think this thread would exist.

Anyway back out to the garage now to carry on with the clean / build.

Thanks for all the good advice.

Cheers

Mark

[Rich]

Money well spent for the fuel analysis. It probably goes lean 'cos you shut the throttle to change gear = no fuel going in.

[Taffus]

Gents; (Reading Branch, Bramley) they told me that they keep stocks of jets for all the major carb manufacturers.

They do this for a living and do it all day every day.
Based on the £40 assessment that you see above they can tell exactly which jet needs to be changed, which parameters need to be altered and which settings need to be adjusted.

I would anticipate that they would get it right first time and i believe they offered me this service based on a £35 per hour charge rate or thereabouts to re-set and re-jet.

They change the jets required whilst the bike is sat on the dyno and run it up again afterwards and give you a new graph showing the new settings and new ratio / power output.

I didnt have mine re-set because i was about to have it bored oversize, i only had it done because my friend paid for it after he had his done and was super impressed.

I dont know how you value your time but i spent the next few months trying to get mine right before it was bored out. They do it in half an hour or so and you only pay for the jets you end up with!

VFM i believe.

They also sell and fit power commanders / dyno jet kits, and tuning bits / tyres etc etc.

May also be worth mentioning that they have bust times of year when you need to book a month in advance!!


Hope this helps.



AL

Thanks Al just what I was looking for

[debben1]

You can tell a lot from the all gear run, the graph above shows a dip on the initial climb which is often the case when a bike is running rich at lower rpm, the fact that the power is dropping off fast with each gear change indicates leaness (by the time top gear is reached power has fallen off dramatically) this leaness can come from fuel tap not flowing enough, air restricted into the tank breather or just lean settings with in the carbs.
The latest air fuel ratios are a good guide but they are only a guide, the perfect air fuel ratio varies between bikes gears, and even different rpm, ie there is no fixed perfect air fuel ratio magic number, modern ecu's with closed loop systems now let you set a target air fuel ratio for differnt gears and rpm, sometimes the perfect air fuel ratio is as low as 12:1
Regards, Steve

[zedrider]

ive had something simular happen to me . i got a full set of new pistons rings etc . but the next size up from standard . but for the price i paid i thought no problem . so i went to numbpty engering . all i shall say is dont asume that just because they work in an engering firm they know what there doing . new pistons new rings all shot and why ? the bores wernt honed . could be something simular ?

[Mark Stratton]

Rebore and pistons bought from Debbens so absolutely no worries about quality - you only got to look at their race bikes to realise they know what their doing. The problem with mine would appear to be ignition for what everyone is suggesting - just hope the bores and pistons are useable or I will have to find some second hand ones so that I can get it back on the road.

[zedrider]

pitty pete williams aint open anymore down nr the train station . i took in my z650 a few years ago running rough as hell . the main man him self sorted the problem . ive no idea what he did but i swear it was like a diffrent bike . after he finished . as you may have gathered i was local to southampton then .

[zeroed]

if there`s a weak spot 9500rpm will find it, at least it didn`t seize solid and your ok.