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Offline Ivan

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Re: DIY snatchy Throttle cure?
Reply #10 on: November 22, 2019, 12:54:35 AM
Nothing wrong with checking the sensor.... the trouble is that there is no specific voltage... it's only given as an acceptable range.

The range is huge in terms of actual effect.

Try setting it at the minimum and ride the bike and also at the maximum... the difference is profound. These are set up at a particular throttle plate opening and specific voltage... trouble is they don't give that information.  Lol

Offline Notsoaverageguy

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Re: DIY snatchy Throttle cure?
Reply #11 on: November 22, 2019, 05:09:33 AM
Yes when I get home I am going to check my sensor readings and post the results. If anybody else does the same thing maybe we can get a graph and see if the correlation matches feelings from other people. If nothing else it will be fun and interesting. Wonít be home till mid December   :006: Man I miss my bike.
Things should be made as simple as possible, but no simpler!
(Albert Einstein)

Offline Notsoaverageguy

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Re: DIY snatchy Throttle cure?
Reply #12 on: November 22, 2019, 05:30:37 AM
Ivan, your right they give a huge window. One of the reasons is partly for the exact same reason I pointed out. I didnít get into this part cause my post was long already. But when manufacturers order their sensors (that they themselves donít make ) they pay for an ďacceptableĒ window of failure and accuracy. They settle on a cost that matches the level of bike (or car) they are marketing. So when you add up all they inaccuracy of all the sensors acting on the engine if they set a must have number hardly any sensors when combined would be in spec. Agreed they do try and give a large enough window of acceptance in the map but it doesnít always work out.
EFI system when running looks at
TPS
CTS (coolant temp)
RPM
MAP (manifold atmospheric pressure)
ATS (air temp sensor)
O2 sensor
Speed sensor
And so on......  I do believe that some are more sensitive to the feeling than others but I do think it can be improved. Kawasaki did not give the green light (ha joke intended) on a jerky on off feeling on a bike they where going to sell as having a nostalgic look and feel to the original carbureted model. There test or beta bike had a perfect map, and I know for a fact if you looked at enough bikes on all there sensors, -many will match up to original design. Maybe you could put some on that  perfect map bike and they might still feel ďsnatchynessĒ. After all it is NOT a carbureted engine. The reason we donít feel on and off in are family car is partly due to the fact there is so much weight being pushed and shoved it dampens a lot of the feel.
Just saying
Last Edit: November 22, 2019, 05:33:35 AM by Notsoaverageguy
Things should be made as simple as possible, but no simpler!
(Albert Einstein)

Offline Ivan

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Re: DIY snatchy Throttle cure?
Reply #13 on: November 22, 2019, 06:56:05 AM
There was a test or beta bike had a perfect map,

That bike wasn't emissions certified.

There's one other thing that I noticed about the throttle bodies is that the cable pulley is round.... Most bikes these days have eccentric pulleys.

I haven't seen a round pulley in a long time.

Last Edit: November 22, 2019, 07:01:20 AM by Ivan

Offline Oop North John

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Re: DIY snatchy Throttle cure?
Reply #14 on: November 22, 2019, 08:51:29 AM
*Originally Posted by Ivan [+]
There's one other thing that I noticed about the throttle bodies is that the cable pulley is round.... Most bikes these days have eccentric pulleys.

I haven't seen a round pulley in a long time.

Would a throttle tamer replicate the eccentric pulley? One like this: https://www.g2ergo.com/shop/g2-street-tamer-throttle-tube-kawasaki/

And do you think it would have any beneficial effect, apart from a possible placebo one?

Offline luishcorreia

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Re: DIY snatchy Throttle cure?
Reply #15 on: November 22, 2019, 10:02:48 AM
*Originally Posted by Notsoaverageguy [+]
Sorry this is going to go long. But if you suffer from what you think is a snatchy throttle (i dont, 2018 Cafe California) you might want to read this. First I will give my background so you can discern it is my pie hole I am talking out of. I was a Ford tech from before FI existed in production automobile, and was there for the learning curves, both Techs and the factory. They had same drivability issues as some of you are experiencing. I mean the exact same!!! meaning some customers complained and some didnt (most) on the exact same cars. Which got me to thinking why do some say they have it and some say they dont? And it dawned on me, maybe its the same problem as before. FIRST let me clarify I do NOT know this is the problem but got a pretty good idea and will explain why I think so.
1) EFI systems are all the same in the fact that they all run on sensors and processors that have perimeters. And yes re-flashing a computer  will sometimes cure it but its only really masking the cause. We had MASSIVE problems with TPS (throttle possition sensor) and throttle plate settings that drove everybody bonkers. They would set a perimeter in the processor and for safty and idle purposes it had to be a tight tolerance, that didnt always match the MAP and would piss off the computer which retaliated in lousy drivability.
Recently experienced this on my 06 ZX10R and immediately recognized the problem, and on THAT bike fixed it very quickly.
2) These problems are from idle stop onward. Maybe you dont recognize it as being that but I am willing to bet, that it is between the gears and when you are on and off the throttle. I again havnt ridden a RS with the problem so this is the big "IF"
 
Here is what is going on. The MAP says when the throttle plate is closed (fully warmed up and not using secondary butterflies or ABV (air bypass valve) the TPS should read ;example/ .45 volts. Great in the imaginary world of the engineers. Problem is (and I did have to adjust my idle screw because of occasional stalling) all the idle stop screws and TPS dont match up exactly. I am not going to go into why they dont, its cost related, nuff said. So when the computer sees the throttle plate closed and the TPS where it is not supposed to be it gets pissed off and runs its own map! The fix is easy TRUST ME.
By the book you would hook up a DVOM to the sensor lead + and ground the negative, find out what those engineers had in mind and adjust it to match (provided you idle was already set) and off you go. A much easier method on our RS is (the sensor is right there on the left side easy access. Loosen the 2 screws I think its marked in it present location, and move it one way or the other (make a note) just a touch. Go and ride. You can do this on the rode.  NO you cant hurt anything. Adjust till you make the computer happy. Again I had the exact same problem on my ZX10R. Much harder to get to the screws but it was solved.
Anyone can do this if you know how to run a screw driver (hand held no gun please) I am away fro home now so dont have access to Mona or I would get the DVOM readings for you. So if you do this and are successful please pass it on to the rest.
Just saying.

NO ... i didnt understood anything. Can you explain whats te step by step actions for us layman?

Offline Ivan

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Re: DIY snatchy Throttle cure?
Reply #16 on: November 22, 2019, 11:26:02 AM
*Originally Posted by Oop North John [+]
Would a throttle tamer replicate the eccentric pulley? One like this: https://www.g2ergo.com/shop/g2-street-tamer-throttle-tube-kawasaki/

And do you think it would have any beneficial effect, apart from a possible placebo one?

Definitely a placebo...

Please watch the videos that I posted above and you will fully understand the whole thing.

The eccentric pulley (throttle tamer) will make it feel less sensitive in the way that it will require more movement at the grip to maintain speed and light acceleration, but the delay and "hit"will still be there when the injectors come back on.

Can't change physics unfortunately.

Offline Dirty Dave

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Re: DIY snatchy Throttle cure?
Reply #17 on: November 22, 2019, 12:16:38 PM
I just have to say how much I appreciate Ivan's input to this group.

  :047:
18 Z900RS Jaffa
97 Honda Valkyrie
79 Honda GoldWing

Offline Ivan

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Re: DIY snatchy Throttle cure?
Reply #18 on: November 22, 2019, 12:25:07 PM
I expect to take delivery of my new cafe tomorrow... so now I'm going to have both RS models... 😉

Offline Notsoaverageguy

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Re: DIY snatchy Throttle cure?
Reply #19 on: November 22, 2019, 03:45:25 PM
Yeah so I watched the videos IMHO doesnít match what I am talking about. 1st thatís not our bike and 2 I donít know what other modifications are on that bike. My bike NEVER backfires like that. It looks to me to be a lean misfire which most assuredly can come from shutting fuel down, but is usually preceded by a lean mixture to begin with. AGAIN  I am not saying that a reflash is bad or wrong for that matter. Simple a band aid for something else. I would love to see that same test done with our stock bikes. With that said all I am offering is a possibility to those who want to tinker. And I am sorry if all the explanation is over someoneís head. It might be best for them to reflash if they didnít understand what was said.
Just saying
Things should be made as simple as possible, but no simpler!
(Albert Einstein)