light load surge finally nailed

[Ward P]

I would be interested in comments by "those that know" (those in the game) as to the above. Took it for another ride today and it was sweeeeet! - but it was intermittant before, so I'm waiting to see if the "surging" re-appears.

[rb3221]

Any more word on surging, my mates 99 has just started doing it and I am trying to fix it for him. I have tried everything that has been talked about here and no change. It only does it at low throttle around town and at highway speed, even tried taking out the pink wire.

[fasterfaster]

Re map it

[rb3221]

[Legend]

[rb3221]

[fasterfaster]

No pink also cuts out the high speed enrichment.......... your prob could be as simple as the the fuel hose routing being incorrect to return filter being blocked etc etc .............. simply a matter of going thru and checking all possibilities. Note again hose position and routing on the 99 is critical especially making sure the inlet line runs straight and horizotal across the top of the gear box with no up and downs.

[Legend]

[rb3221]

[Legend]

[Katana2]

Everyone of you know more than me. But my '99 did have low fuel load 'surge' problem. What i experienced (probably still do, but I don't let it run at low level any more) was not related to throttle position. It would cut out at tiny speed and on very partial throttle, and with throttle pump (twists of the thottle), come good after time. In this mode, it also would flutter badly at 6,500 or so, and not fire properly to the poinnt of not accelerating at all. It would not motivate at next to no throttle, or max throttle. I took the lower fuel line on the tank off the tank at low fuel lovel, and fuel just drops out. It can't be a filter problem otherwise it would happen at high and mid fuel loads also. Please don't think this is only a partial throttle problem, because it's not. If i need power when i am on low fuel load, and don't get it... could be a real problem. I don't know what is causing this problem is though.

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PS. My busa is bog stock. Standard exhaust, only K&N air filter. No other engine, intake or exhaust mods.

[Greeny_SA]

Everyone of you know more than me. But my '99 did have low fuel load 'surge' problem. What i experienced (probably still do, but I don't let it run at low level any more) was not related to throttle position. It would cut out at tiny speed and on very partial throttle, and with throttle pump (twists of the thottle), come good after time. In this mode, it also would flutter badly at 6,500 or so, and not fire properly to the poinnt of not accelerating at all. It would not motivate at next to no throttle, or max throttle. I took the lower fuel line on the tank off the tank at low fuel lovel, and fuel just drops out. It can't be a filter problem otherwise it would happen at high and mid fuel loads also. Please don't think this is only a partial throttle problem, because it's not. If i need power when i am on low fuel load, and don't get it... could be a real problem. I don't know what is causing this problem is though.

---

PS. My busa is bog stock. Standard exhaust, only K&N air filter. No other engine, intake or exhaust mods.

If the small round, plastic gauze filter in the fuel pump gets blocked,99& 2000 only ( external pump's ) it causes all sorts of problems, 1 being excessive fuel consumption ,another poor running.
For the 5 buck's they cost & 10 min to fit , I change mine regularly .

[rb3221]

[rb3221]

What reading should you when you test a TRE with a meter.

Ran the motor up to 2000 rpm's and pulled the clutch and the revs dropped when the clutch is pulled.

[Legend]

What reading should you when you test a TRE with a meter.

Ran the motor up to 2000 rpm's and pulled the clutch and the revs dropped when the clutch is pulled.

To be honest, I use a 10c resistor (5.6k ohms) to do the job. I would "assume" the resistance of the tre would be the same (5th gear gps resistance).

It sounds like yours is working ok thou.

Leonard.