[Wozza]

Hi everyone
Wondering if anyone can advise me which way to go with stopping my monster from pining under 3.5k ish rpm under slight load
This is the ingitech map Im using.

The info on cycleworks coils say you might need to use DR9EA plugs (currently running DCPR8E plugs)
So do I plug swap or do I lower the ingitech map points (or do both) if so by how much?

Thanks in advance for any info or advise
Wozza

 

[Mal’s900SS]

One heat range “colder” (runs at the same temp but at a higher operating temp)

but d= 12x1.25 18mm hex
Dc= 12x1.25 16mm hex
P projected insulator
r resistor
E= 19mm reach
A = special electrode

I was always taught to make ONE change at a time or else you don’t know what made any difference, sometimes one cancels the other.

 

[wdietz186]

Maybe richen it slightly, without having the chart handy I think it's in the transition from pilot circuit/slide cutaway range. FCR's also have an adjustable air jet on the inlet side of the carb. As I recall my 900 race bike was too lean on initial throttle opening and I went up a size or two on the pilot but I never rode around at revs that low.

 

[RockAZ]

Stock pistons size and compression, right?

 

[Wozza]

Thanks for the replies
No idea what the internals are (only had bike a few weeks)..from the paper work the orig owner gave me, lightened flywheel is the only thing I can see
cheers
Wozza

 

[RockAZ]

Well, you could check for flat top pistons or domed? Helps to know what you are tuning for. If the paperwork looks complete, then it is probably stock.

 

[Wozza]

Hi
from what I can see flat top pistons...
Im at a loss what to do now
Plug change did nothing
tried lowering/extending timing to this..

so to recap/ update
carb settings
Fuel screw 1-1/4 turn
Slow Air Screw 1-1/2 turns
Float height 9mm
Main Jet 155
Main Air Jet 200
Slow Jet 60
Needle EMT
Needle Clip 3rd from top
Plugs DCPR8E

compression check 135rear 140 front
timing mark lines up at idle and is stable
So what am I missing, after all the above it still pings ...grrrrrr
Thanks
Wozza

 

[Mal’s900SS]

You’re doing pretty well to hear the pinging with helmet on, riding, over the carbs , over the exhaust.

Can’t be on a free rev as pinging is only there under load.

what fuel are you running (exactly please), how old is it, how much did you add this time, does it smell like good fresh fuel,

get us a picture of both plugs after a W O T run in 2nd gear, shut the engine off and coast to the side, remove and photo them, your choice to refit or stick your old ones back in.

 

[Mal’s900SS]

But pinging should only be under load so the advance curve might be out.

I’m wondering if you’re hearing something else mistaking for pinging.

 

[Wozza]

If its not ping,Im in trouble lol.. been tinkering and building bikes since the 80's so Ive end up with a sort of tuned ear
Funny you should mention fuel. full tank filled only a few days ago. I was thinking tonight its something I havnt ruled out. so tomorrow Im gunna drain the tank and put in some fresh 98 from a different servo in case its bad batch (or I had a senors moment and put in 91)

 

[Mal’s900SS]

It should run better on 91.. but rule out the Ping first

 

[ducvet]

Stock motor?
why not run stock ignition boxes ?
not sure of fuel in Australia but in the US I would run a stock motor on 87 octane.
bottom line the stock bike should not ping with stock boxes so either there is something wrong with the ignition or something is wrong with the bike.
Before you go any further....

check head nuts for one that spins free (broken cylinder stud).
Check the chain for tension or a modified swingarm angle (ride height increased from stock). A chain will whip when throttle is addend from steady and if the chain is loose you may be hearing the chain slap the swingarm.

 

[Mal’s900SS]

87=91 here

 

[wdietz186]

As an experiment try running in the slow air screws 1/2-3/4 turn, it should richen the idle jet/cutaway transition. As ducvet said, checking the chain and muffler mounts etc. for a possible harmonic rattle too.

 

[Wozza]

Thanks everyone, keep the suggestions coming
Pretty sure the noise in pinging,either that or carb slides rattling or metal parts rattling around in the combustion chamber
Have drained the tank\carbs and refilled with 5l of fresh 98 fuel...the fuel was a different color so hoping this is all it was ....nah its never that easy and unleaded changes color with age
The manual says to run 95 or 98 ron anyways it raining cats and dogs here at the moe, but fri might be okish for a test ride.
Been googling the F out of the issue and came across a post on this site
Ignitech Map : 900SS + FCR41 + light flywheel
the kokuson map (in pic) interest me as I would have thought it would have had a few more changes in deg over the rev range...meh something to try if the fuel isn't the issue
Thanks Again
Wozza

 

[wdietz186]

Re reading the posts, it's a very good possibility you are hearing the slides in the FCR's rattling. Light throttle, relatively low rpm and strong vacuum pulses will bang them back and forth in the bodies pretty hard. I think the light flywheel would just amplify things too.

 

[RockAZ]

The slides make more of a "clack" noise, sometimes, "clackity-clack" - I would not confuse it with pinging. Yes, my bike can ping on super hot days with hard running in the desert - uphill WOT with 89 octane fuel. 91/92 usually eliminates it without any carb changes. I'm talking +115F heat making the road surface temp above 150F, just waves of heat, mirages in the distance kind of misery to get through as fast as I can. So, yeah, pinging, I know what it sounds like, but not sure what OP is hearing because it doesn't seem like he is experiencing the right circumstances to cause it.

 

[Wozza]

Well im outa ideas, nothing I do really stops the noise...the carbs are newish and Ive changed all the regular stuff (getting quite a jet collection here )
fuel flush made no difference...started pulling advance out of the curve bike runs like shit but still the rattle..hold front brake on and feed in revs and clutch..no rattle???
so either the ignitech unit is failing or its some other rattle...I may run with the pod filters off, if sound gets louder then its prob carb slides
thanks

 

[RockAZ]

Free floating brake rotors? Maybe one disc bolt is too loose or too small? Missing anti-rattle piece in brake pad? Loose fender or even rubbing tire on fender? Loose or broken oil cooler mount? Loose reg/rectifer mount?
I don't think what you are hearing is pinging, but it might point to something aluminum making contact with something steel.

 

[Wozza]

I am checking all the suggestions as I know sound can travel and echo, but my gut is saying its coming from engine area
The ducabike slipper clutch has also been making weird noises, so checked that and its toast ...just ordered a clutch pack from fastbikegear, no more road testing till thats installed.
No idea how long post from UZ takes, but rearsets from the UK took 3 weeks.....
thanks
wozza