had bike on dyno has got 75bhp @wheel,air fuel ok and both cylinders at same temp.tried different eprom but no joy,any suggestions guys?:dunno
Restricted, Lift the tank , remove the lid from the airbox, remove the airfilter and check the size of the opening under the filter it should be about 4 inches in diameter if it looks like there is a plate with about an inch diameter opening its restricted (standard euro spec I think).
How do you know the eprom was a good one ?, also is the little blue wire from the ecu cut ?
There is probably 10,000 other things to check but start there.
How do you know the eprom was a good one ?, also is the little blue wire from the ecu cut ?
There is probably 10,000 other things to check but start there.
airbox got approx 4"hole under filter and the chip out my mates bike it made good 120bhp@wheel,the wire is cut to?
You sure that the rear brakes not stuck on? :doug
No seriously, to lose that much BHP at the wheel must be something serious, had you not noticed that you couldn't keep up with the rest of the pack?
First thing I would check is that the drive trains not sapping the power, then start looking at the power plant.
Make sure all the engine is set up correctly, TB balance, CO settings are correct and that the plugs are all in good condition.
TBH it could be a thousand problems and if your not technical it may be time to pass the bike over to an expert.
Where are you in the country? Griff may not be far away from you.
i have my own tuning shop in scotland been on go for 12years mostly building bsb supertock and supersport bikes,just thought id ask you guys as i havent had any problems with any mille,s,i have balanced throttles bodies done plugs clearances etc all drive line ok
thanks
thanks
Not sure even a restricted bike would put out that little power.
assuming it has been de restricted and on what you just said it has to be a motor problem. The valve clearances can get tight if they are not checked but generally the motors are pretty solid.
assuming it has been de restricted and on what you just said it has to be a motor problem. The valve clearances can get tight if they are not checked but generally the motors are pretty solid.
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Cool, so you have the tools and know how you now just need some ideas.
Few more questions:
1. Was the clutch slipping under load/high RPM?
2. Has it still got the standard exhaust fitted? (Very restrictive to flow)
3. Is it and early mille engine fitted to an 01 bike? (small valve)
4. What did you set the CO to and how did you adjust it, mine was a pile of poo until I tweaked the CO up.
5. Could it be that someone has done the valve clearances and got the timing marks out of alignment?
Food for thought hey!
At what temp dit you test it?
The aprilia eproms have enrichment in em.
It's like a U curve.
Rich cold up to 54, and starts to get rich afther 86 again.
Take a fuse and connect the fanswitch connectors to buy you some time.
The aprilia eproms have enrichment in em.
It's like a U curve.
Rich cold up to 54, and starts to get rich afther 86 again.
Take a fuse and connect the fanswitch connectors to buy you some time.
yes dyno working fine thanks ,had the bike up to temp ok gave it 15,20 runs .think im going to pop engine out and have a proper look,treid different bodies,tank today and it still crap
for your interest i had a rsv 4 on my dyno very impresive the bike made 160bhp@wheel and it had only covered 150 miles the bike is racing at north west 200 today(mike skinner)
if you guys want i can post dyno graph on monday
thanks stuart young
for your interest i had a rsv 4 on my dyno very impresive the bike made 160bhp@wheel and it had only covered 150 miles the bike is racing at north west 200 today(mike skinner)
if you guys want i can post dyno graph on monday
thanks stuart young
Joined Aug 2008
3K Posts | 0+
Brittany France
Th Mille in restricted form will push out 107 bhp ( french law)
You said that the chip from your mates bike made your bike up to 120bhp? so it must be the chip???
You said that the chip from your mates bike made your bike up to 120bhp? so it must be the chip???
no sorry the chip in his bike produced 120bhp when i swaped it over the bike still made 70 odd bhp
robbiersv here, just to let you know its my bike that is in question and i,m not happy.i,m a time served car mechanic serving my time onold school rolls and bentley,s so su carbs and fine champagne are no prob. how ever italy,s finest twin is pissing me off. here,s the low down. bought bike in november. spent small fortune cosmetically. fitted iridium plugs due to what i read ref low voltage high, high spark. its got no air intake restriction ie as per later models and has k&n. as to the eprom i checked today and had an aftermarket performance one fitted. i so happened to have bought one when i first bought it but never fitted it until today as a process of elimination but has made it if anything slightly worse. so that,s not prob. was suggested by stuart that perhaps fuel pressure prob but asi,ve said before it starts, and drives through the rev range without a cough or hessitance, only about 40bhp down on what it should be. it,s like i,m running on a map for wet weather.get it? as for the exhaust i,ve run it on andirsv,s ex arrow ti race pipe and it,s now got a proper aprilia shotgun ti race end can set up. its also got days old sprockets with well lubed chain. ( i,m an ex racer of lc,s/powervalves). if you jumped on it you would think it ran fine but was restricted for a foreign market. next level of suggestion,s appreciated. robbie
Joined Apr 2009
93 Posts | 0+
Bromsgrove
I would be interested to see the power curve and fueling curve if you or stuart have one. I would suggest get back to basics. Compression test, ignition and valve timing checks. I would say the fueling curve could be critical to see, as many of the possible faults will show up in poor fuel mixture. (PS I own a bike shop in Warwickshire and we have a dyno)
Good luck.
Good luck.
Sorry to hear your bike wows mate but as said before, go do the basics first.
Are the valve clearances correct?
Is the valve timing correct?
Compression values correct?
Once you've checked these and they are confirmed to be within tolerances then start looking at fuelling spark etc...
Let us know what you find.....
Are the valve clearances correct?
Is the valve timing correct?
Compression values correct?
Once you've checked these and they are confirmed to be within tolerances then start looking at fuelling spark etc...
Let us know what you find.....
Here's my dyno chart for my old Mille for comparison, '99 with Renegade Airbox fitted, and Micron exhaust. Rest standard. HTH:
Could itbe the ecu, 5000 rpm is where they normally test the noise/emisions and this goes flat at 5000.
Any chance you could swap the ecu with your mates bike you borrowed the chip from and see what happens on the dyno.
Or has the wrong blue wire been cut?
Any chance you could swap the ecu with your mates bike you borrowed the chip from and see what happens on the dyno.
Or has the wrong blue wire been cut?
Got mine tested today for free.
134 bhp the old lady seems to be fit.
Some "ditches" around 5000rpm.
I have been planning to take her to be adjusted.
Synchronizing of the tb:s needs to be done as well as the CO2 adjustment. If they are incorrect could it be the reason for 5000rmp ditch?
In my neighborhood there is one Aprilia specialist and one normal garage I am tempted to take her to normal one. What would you recommend.
Yes because it was free no printout was given.
134 bhp the old lady seems to be fit.
Some "ditches" around 5000rpm.
I have been planning to take her to be adjusted.
Synchronizing of the tb:s needs to be done as well as the CO2 adjustment. If they are incorrect could it be the reason for 5000rmp ditch?
In my neighborhood there is one Aprilia specialist and one normal garage I am tempted to take her to normal one. What would you recommend.
Yes because it was free no printout was given.
