[Masternaut]

Been flogging this bike as my daily for over a year now. It's mostly good except one tricky issue I have not been able to track down. Riding along normally in second gear for instance if I suddenly whack the throttle wide open above say 3k rpm it sometimes doesn't accelerate fast at all (almost zero accel) and just casually will rev all way to 7-8k extremely slow. However if I roll onto it but still pretty fast it's perfect and doesn't have this issue. Only noticing it in second gear too.

Clutch? No, it's not slipping one bit. Bites great and shifting from 1st to 6th full pin is flawless.

Fuel? I have a power commander in there with a map for aftermarket exhaust. With or without the device connected the problem still exist.

Spark? I put new plugs in recently. Battery age is unknown but starts great even on 10 degree days. A coil could be cracked causing a short? Looked good when I pulled them.

Oil? Doubt this would have anything to do with it. I run Amsoil full synthetic in there since I bought it with 5k miles.

Chain? I do all this work my self, chain is tensioned correctly and is now getting replaced again with front/rear sprockets.

Valves? Yeah they probably need checked but this problem was here way before 15k miles.

Air Filter? Clean as can be.

Mods related to engine. Full Delkevic exhaust, synced throttle body with jumper tube, removed the secondary throttle plates.

History. This bike has been in deep water, snow, mud, salt, jumped ect all the elements all year round.

I checked the TPS and adjusted it using the Power Commander Software, all is good there. Throttle cable might need to be tightened up a bit but this is not the issue. Breather that connects to airbox is leaking, needs replaced.


Any ideas would be greatly appreciated!

 

[waspmike]

if I suddenly whack the throttle wide open above say 3k rpm it sometimes doesn't accelerate fast at all (almost zero accel) and just casually will rev all way to 7-8k extremely slow. However if I roll onto it but still pretty fast it's perfect and doesn't have this issue.

Sounds as if the fueling does not have an "accelerator pump" type setting or function. Like the Yellow mode with a Dobeck EJK.
What happens if you roll on and then go wide open? Maybe the TPS is bad or dirty at wide open?

 

[Masternaut]

Sounds as if the fueling does not have an "accelerator pump" type setting or function. Like the Yellow mode with a Dobeck EJK.
What happens if you roll on and then go wide open? Maybe the TPS is bad or dirty at wide open?

Rolling on even pretty fast works perfect. I know about that setting you're talking about too but my chip doesn't support it. TPS sensor voltages are just fine!

 

[waspmike]

OK Just ride around the problem and live happily ever after.

 

[Masternaut]

OK Just ride around the problem and live happily ever after.

Yeah for me it's not quite like that lol. There's def "something" going on and there's no reason it cant be fixed.

 

[waspmike]

My two-stroke bike has different ignition maps for different gears? Just sayin... As yours only happens in second?

 

[Masternaut]

My two-stroke bike has different ignition maps for different gears? Just sayin... As yours only happens in second?

I have only ever noticed it in second, likely its happening in other gears as we 3rd, 4th ect. Doesn't appear to be an option to adjust per gear in the software!

 

[waspmike]

I think you are chasing ghosts!

 

[Masternaut]

I think you are chasing ghosts!

I wish I was man but it straight up dies with power when I hit it really fast. And It does it every single time. Gets really annoying. It's not like a small power loss it's like the rpm's go up and then it just hangs there until I let go and re apply throttle. It's bad enough that I made this post lol I wouldn't be wasting my time or anyone else!

 

[OtherRoad]

I'm guessing, don't have a Versys 650 yet, but plenty of motorcycle experience.
I think you nailed it.
"Breather that connects to airbox is leaking, needs replaced."
It is tuned for the air box.
A sudden application of throttle makes it go lean momentarily.

 

[Masternaut]

I'm guessing, don't have a Versys 650 yet, but plenty of motorcycle experience.
I think you nailed it.
"Breather that connects to airbox is leaking, needs replaced."
It is tuned for the air box.
A sudden application of throttle makes it go lean momentarily.

I never thought it could actually be a problem but I will replace it and see what happens!
Good idea!

 

[fasteddiecopeman]

It's not like a small power loss it's like the rpm's go up and then it just hangs there until I let go and re apply throttle.

THAT sentence sounds to me like your clutch is SLIPPING...!

 

[Masternaut]

THAT sentence sounds to me like your clutch is SLIPPING...!

18k miles, Amsoil since 5k miles? Idk about that. It's done this since I had it! Sorta doubtful on that.

 

[Masternaut]

THAT sentence sounds to me like your clutch is SLIPPING...!

Also why it's not the clutch. When this problem happens the rpms go up extremely slow. if the clutch was slipping it would still rev fast but with no accel!

 

[onewizard]

Haven't looked at the service manual, but the fuel pump pressure would be the first thing I would look for.
There have been a few similar posts over the years, in most cases it was the fuel pump.

 

[Masternaut]

Haven't looked at the service manual, but the fuel pump pressure would be the first thing I would look for.
There have been a few similar posts over the years, in most cases it was the fuel pump.

I also thought of this. Checking it shouldn't be too hard!

 

[Masternaut]

I turned the voltage up a little bit on the TPS from 1000 to 1030, running just a little more rich now. I think 1030 is the highest it should be. Seems to be much better? I had more fuel +20 on low and mid with the PC and it still had that problem though so not sure why this would make that problem be less noticeable. Will keep testing. Maybe it's got to be spot on with fueling!

 

[onewizard]

lots of info here

Throttle Position Sensor/TPS/Modification / MK-1 MK-2...

My main throttle sensor voltage was at 1.061 V at idle throttle opening (standard: 1.005 - 1.035 V), and 4.03 at full throttle opening. (standard: 4.2 - 4.4 V) So I decided to set full throttle at 4.2 V, which gave me 1.091 V at idle. This raised idle speed and fast idle speed a bit which I the...

www.kawasakiversys.com

 

[Kris]

if you are in USA (or EU) reflash your ecu with VERSYS 650 Mountain Runner ECU flash - Shoodaben Engineering

I mean with O2 removed, and Booster Plug the bike was running ok. but for the price, ECU flash is so cheap and so great.

I say 'if you live in USA' because I was ripped off on the import taxes.

 

[wheels2ride]

Old SV650 issue fix. The factory stuff settings are good, some are not due to passing emission tests.
Try moving TPS sensor up/down from optimum setting. It worked for my old bike.