[HARRIS10071996]

What’s going on fellas, looking for some help. I recently replaced my stps tuned it to factory spec. Bike does not bog anymore. Cleaned all injectors. Also replaced the fuel pump and filter. I’ve heard there is a second filter in the fuel pump housing but I didn’t see one. Anyways, racing my friends on interstate. Maxing my wrist out I have a loss of power on top end. No problems what so ever until I max the throttle. Almost feels like I’m lacking fuel? I have had a guy tell me bad o2 sensor can do this. Don’t know how much this is true. Really just trying to get my bike to its full potential for the strip. It’s completely stock. Exhaust actuator valve is removed and the valve is completely open. Lost at this point. Thanks

 

[Chuckster]

Do the fuel pump inspection test. The main fuel filter is not servicable.

 

[rv6john]

^What he said, likely a quantity issue.

The high pressure (2nd) filter is in that plastic housing next to the pump.

Your K7 did not have an O2 sensor from the factory (that started with the K8 600/750 model.

Also, don't listen to anyone that thinks an O2 sensor affects high power operation.

 

[HARRIS10071996]

I’ve repla

Do the fuel pump inspection test. The main fuel filter is not servicable.

so what you are saying is I need to buy the complete housing new? Start fresh? I just bought the high pressure pump from eBay. I know kick me in the ass later but it was a cheap diagnosis at the time. Bike preforms better just not it’s full potential. Any other suggestions ?

 

[Chuckster]

Some people have bypassed this filter and added an inline filter. Some have backflushed it and gotten positive results. Shame on suzuki for not making this a servicable filter.

 

[Chango]

I’ve repla

so what you are saying is I need to buy the complete housing new? Start fresh? I just bought the high pressure pump from eBay. I know kick me in the ass later but it was a cheap diagnosis at the time. Bike preforms better just not it’s full potential. Any other suggestions ?

Not yet. First you need to do a flow test to make sure the current pump is actually pumping all of the fuel it is supposed to.

 

[HARRIS10071996]

I do have another diagnosis…… my engine revs all the way to red line in neutral… I do have a stretch but would this keep me from going almost redline in gear? Also i am thinking of clutches also… could clutch either be grabbing to much? I do have the slack everyone talks about to prevent prewear but is it not enough where it’s slipping ?

 

[rv6john]

Nice try but the engine needs very little fuel to rev to red line with no load.

The clutch should not slip at all when engaged so there is no such thing as grabbing too much. (some clutches chatter and don't engage smoothly, but that is a different issue).

 

[Tinsnips]

As above, if anything the clutch slipping would be your concern. That would also be noticeable in the lower gears when launching.

Do the fuel flow and pressure tests and go from there. Soaking them gently back flushing the secondary filter with something like sea foam may help.

Just for shits and giggles make sure your fuel lines aren’t kinked or pinched under the tank. I doubt it but let’s rule it out.

 

[HARRIS10071996]

Nice try but the engine needs very little fuel to rev to red line with no load.

The clutch should not slip at all when engaged so there is no such thing as grabbing too much. (some clutches chatter and don't engage smoothly, but that is a different issue).

What is the proper fuel test?

 

[rv6john]

What is the proper fuel test?

It is in the service manual. In short you hook up a pressure gauge and check the pressure, then run the pump for a set time and measure the quantity the pump puts out.

 

[HARRIS10071996]

Replaced my clutches and problem is gone. So much faster! But now I’m having a Slack issue. I did find the chain behind the clutch basket was VERY LOOSE. What is that chain for ?

 

[HARRIS10071996]

When throttling and easing off the clutch is kind of clunks like it is catching gear. I’ve adjusted from inside clutch basket all the way up to the handle bar to what manual says to do. Is that a drive chain?

 

[XPOH]

I did find the chain behind the clutch basket was VERY LOOSE. What is that chain for ?

It looks like an oil pump drive chain
Pos. 18