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91 907ie back fire
Posted: Tue Feb 21, 2006 7:44 am
by 1564
hello , been busy with 2nd toy 90 851w/2k as new cond. question to group my 91 907ie has a shotgun like back fire upon getting of the gas, it will back fire several times...all fluids,belts,values,electrical checks,fuel filter,spark plugs have been changed adjusted and or replaced...it runs very strong and idles well...only issue is back fire...has euro chip,open staintunes and airbox mod., have appointment with local ducati dealer...any thoughts or suggestions :ugh:
Posted: Tue Feb 21, 2006 1:14 pm
by Finnpaso
Have You done ALL needeed adjustments to INJECTION ?????

Posted: Tue Feb 21, 2006 2:35 pm
by 1564
have not touched computer/fuel injection...will have duc dealer sort that out...any thoughts
Posted: Tue Feb 21, 2006 3:16 pm
by Finnpaso
Most of that kind problems are connected to fuel/ignition system, thats why. Read close topic "problem with idling". U have changed/checked near all other possible things, so Injection should check next! Remember, that there are also "not so good" Ducati dealers, who cant find solution to problem, but surely they can take Your moneys easily....
Ps, Injection NEEDS, that Your battery is filled with current and it can also give it to system = Good battery and NOT clogged fuel filter are "MUST" in injected bikes !!!

Posted: Tue Feb 21, 2006 9:41 pm
by DesmoDog
My guess is it's the exhaust and if you check for leaks at the muffler/pipe junction, you'll find one... if not there check at the crossover and then head. Wildcard guess - all of the little plugs are still in the pipes, right?
If the bike's backfiring through the intake you probably have an issue with the mixture. The "Euro chip" probably isn't enough to compensate for the modified airbox and mufflers - you really need an aftermarket chip to keep the bike from running lean. Too lean and you can burn valves...
Posted: Wed Feb 22, 2006 12:51 pm
by Finnpaso
I think also, that Euro chip is NOT enough for open exhaust, intake mod, etc.... It CAN be, that You have lost exhaust valves....

Euro chip WASNT enough in my case, when i changed to open pipes, intake mod, K&N, porting, etc... I had to buy FIM chip, FIM AMB AND tune that hole range 7,4% richer, that it started to function, like should !!! Now its ok

Posted: Wed Feb 22, 2006 9:09 pm
by persempre907
Hi everybody,
also I guess for a ECU problem.
A "shotgun" makes to think about a fuel excess or perhaps a valve problem.
I hope you can to work out this problem.
Ciao
Posted: Wed Feb 22, 2006 10:43 pm
by 1564
thanks for the quick response from all, duc into ducati shop on fri, will update on results.....any way i am pick up the 90 851 today from shop, have to instal staintune and mirrors...weather is great in the s.f. bay arear will be in 70's perfect riding conditions :umm:
Posted: Thu Feb 23, 2006 8:38 am
by Rogero
70 degrees and sunny eh?
Well in the UK it's 41 degrees (F) and a bitterly cold North Easterly is blowing down into South Wales.
Too cold for 907's today - I'll take the car.
Hope the problem is solved, mine is chipped and goes well with open pipes....
Posted: Thu Feb 23, 2006 2:39 pm
by 1564
just for information the 907 has a fim chip and puts out 14v at 5000rpm , new fuel filter and is always hooked up to charger... :rant:
Posted: Thu Feb 23, 2006 7:58 pm
by Finnpaso
Remember to check also COMPRESSION in both sylinders !!!! If its exhaust valve problem, then easy to check with compression test.

backfire prob
Posted: Sat Feb 25, 2006 10:54 am
by The_Duke
Hi there
I am experiencing backfiring also and have just phoned Baines racing in the UK. I myself live in Spain at the moment :neener:
He has advised me that this is poss only due to the air pressure here which is thinner than in England. My bike is chipped and he has advised me to put the standard chip back in which should cure the problem.
From experience of living in the UK, the Duke hates the winter and has experienced the equivilant of carb icing too
Posted: Sat Feb 25, 2006 5:08 pm
by 1564
70degrees in s.f. bay area 907 in shop for fuel injection check up o what to do, let see shall i drive the 67 mini cooper s or the bmw k1200gt, i know i will take the 90 851 superbike out for a ride thru the skyline highway, road thru the giant redwood trees...and than over to the beach for clam chowder soup at the davenport cash store...have to be back before wife gets off work....and find out i have been playing
Posted: Sun Feb 26, 2006 7:18 pm
by 1564
per the duc.shop problem seem to be be the fuel injection is way to lean causing problem, not sure how it was set up in lean condition, but anyway they are syn.fuel inj. and feel that will take care of problem...i am looking foward to test drive as it ran really strong in lean condition so it should really have noticeable inprovement in performance...any way will advise after pick up....recomm. if you get a used bike be prepared to spend time and money getting it to up to factory spec. i purchased the bike for $5,000 in reported excellent condition with no problems....it had no major problems but i went thru all preventive maintence(fluids,value adj.plugs,chain etc. and now f.i. system) spend approxly $2,000 in getting to factory spec......well worth doing i have not seen another 907 within area....could have purchased a newer used jap. bike for the same money,,,,but it brings joy to me as they say "other bikes you start, duc' you bring to live"
Posted: Sun Feb 26, 2006 7:37 pm
by DesmoDog
[quote="1564"...has euro chip,open staintunes and airbox mod., [/quote]
1564 wrote:...not sure how it was set up in lean condition...
Not a big surprise really. The Euro chip isn't intended to be used with a modified exhaust and airbox.