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Carb convert.

Posted: Fri Oct 22, 2010 10:16 pm
by ottovalvole
Hi
Has anybody scrapped the injection system and put on carbs instead?

Re: Carb convert.

Posted: Fri Oct 22, 2010 11:29 pm
by angelix
ottovalvole wrote:Hi
Has anybody scrapped the injection system and put on carbs instead?
whay would you do that? does not make any sense.

Re: Carb convert.

Posted: Sat Oct 23, 2010 6:42 am
by persempre907
I agree, but I know someone does it for historic challenges.
I would'nt do any challenge with a Paso...

However, it would'nt be too hard, because you can employ all the parts of a Paso 906 which shares the same engine, but carbed.
Ciao

Re: Carb convert.

Posted: Sat Oct 23, 2010 8:25 pm
by ottovalvole
angelix wrote:
ottovalvole wrote:Hi
Has anybody scrapped the injection system and put on carbs instead?
whay would you do that? does not make any sense.

It is just a thought, it might be a sloution for some of the members on this forum who struggels for months, perhaps for years with malfunctions related to the injection system, poor drivability, irratic idle etc. They spend more time in the garage than on the road driving these fantastic motorcycles.
I bet there are 907`s out there which are abandoned deep in a corner in the garage due to this. Collecting dust and perhaps never get to life again.
Why should a pair of Keihin FCR be wrong?

Re: Carb convert.

Posted: Sun Oct 24, 2010 10:22 am
by persempre907
ottovalvole wrote:I bet there are 907`s out there which are abandoned deep in a corner in the garage due to this. Collecting dust and perhaps never get to life again.
Why should a pair of Keihin FCR be wrong?
I bet there are much more 750 & 906 abandoned in a corner of the garage than 907 due to carb issues... :mrgreen: :mrgreen: :mrgreen: :mrgreen: :mrgreen: :mrgreen: :mrgreen: :mrgreen:

Ciao

Re: Carb convert.

Posted: Sun Oct 24, 2010 10:47 am
by 907pasonut
I fully agree with you Frankie, overall the 907 is reliable I never had to push it and it always took me back home :thumbup: :thumbup:

Re: Carb convert.

Posted: Sun Oct 24, 2010 4:50 pm
by Finnpaso
If 907 injection is maintained well and all parts function well, it beats absolutely all carburator systems(especially P7 in 907IE, as it was designed for factory racers, like 888 in that time period)... Most importand is cleaness in injection systems! I talked one time with such guy who have played and maintained injection systems at last 25 years and he told that 90% of injection problems are caused by DIRT and SHIT in systems. ...filters, filters, filters... and maybe after every 40 000kms injectors away to maintain table to such maintainer! Also injectors need maintaining..... :smoke:

Re: Carb convert.

Posted: Mon Oct 25, 2010 12:02 am
by Tamburinifan
P7 is a primitive ECU that needs a Memory board to have adjustable chips
& it has no offset map.
P8, in 888 from -93 has that, much better.

FCRs are wonderful, I love them in my M900.

But I wouldn`t try to convert my 907 to carbs, anyway, to much trouble.
Just consider wiring, ignition etc.

Re: Carb convert.

Posted: Mon Oct 25, 2010 9:58 am
by angelix
the conversion is simple, you need:

- a 600-750 (carbed/kokusan version) flywheel and pickups; alternatively you can use the 907ie flywheel but you will need to modify it (15 minutes job) buy removing all the trigger lumps except one which has to be in a "specific position" easy to find by comparing it with a 600-750 flywheel.
- Ignitech Module + Dyna Coils
- MiKuni carbs or FCR carbs.
- a good set jets & needles
- a SS or M900 Airbox
couple of hours on the dyno.

if you really want to make it, I would go for a FCR kit modified with a TPS so that you can link it to the IGNITECH and have MULTIPLE MAPS; there is an FCR kit with TPS already fitted on but will need to be sligtly modified with spacers and jets/needles; SUDCO (also on google there are different posts) can help with that

Anyway, I would NOT change a thing on the 907, the P7 is very reliable and if there are any problems 99.999% of the times is just due to POOR , VERY POOR maintenance.

Often the problems can be addressed to:
- bad pickup, cables become hard with age and tend to break internally.
- wrong pickup distance; the PU need to be within a certain distance from the flywheel to work properly
- clogged fuel filter, it needs changing quite often, it is too small for a 900CC with 80BHP, but is a pain and not always the mechanics (lazy) replace them.
- failing sparkplug wires
- failing TPS sensor or more often , wrong setting.
- wrong CO setting, has to be done toghether with the TPS setting.
- overall poor electrical connections.
- bad P7, it is rare but can happen.

Re: Carb convert.

Posted: Mon Oct 25, 2010 4:13 pm
by paso750
what do you do with the SS/M900 airbox ? There`s no other airbox that fits in the Paso frame specially not those ones. The front section of the Paso frame not as wide as on those models.
Kokusan CDI boxes will work as well.

I don`t know about the 907ie engines but on some newer ones you need to weld some material to the engine case so you can mount the pick up bracket.

I can`t really understand why to carb convert an IE unless the bike is incomplete or the engine is replaced. A bike with FCR carbs rides definetely different though than one with an injection system.

G.

Re: Carb convert.

Posted: Tue Oct 26, 2010 12:04 am
by angelix
paso750 wrote:what do you do with the SS/M900 airbox ? There`s no other airbox that fits in the Paso frame specially not those ones. The front section of the Paso frame not as wide as on those models.
Kokusan CDI boxes will work as well.

I don`t know about the 907ie engines but on some newer ones you need to weld some material to the engine case so you can mount the pick up bracket.

I can`t really understand why to carb convert an IE unless the bike is incomplete or the engine is replaced. A bike with FCR carbs rides definetely different though than one with an injection system.

G.
the SS/Monster Airbox is needed so that you can take the lower part where the bellmouths fit.

Basically out of two airboxes (907+SS/M) you make one to fit your carbs; it sounds complicated, but actually it is the easiest route.

I am not sure about the pickup bracket, although I think shouldn't be difficult.

In any case, I totally agree with you, there is absolutely NO point in downgrading... the EFI on the 907ie might not be perfect but it is much better than any carburator setup.

Actually it could be beneficial UPgrading to a P8...

Re: Carb convert.

Posted: Thu Oct 28, 2010 12:17 am
by Tamburinifan
the EFI on the 907ie might not be perfect but it is much better than any carburator setup.
I disagree. ;)


My M900 f FCR & Ignitech works far better than a original 907 w P7.

I would not change to carbs either, get a good chip.

Re: Carb convert.

Posted: Thu Oct 28, 2010 11:49 am
by 907pasonut
angelix wrote:
Actually it could be beneficial UPgrading to a P8...
how different is a p7 to a p8?...or what are the advantages :huh:

Re: Carb convert.

Posted: Thu Oct 28, 2010 12:14 pm
by higgy
In any case, I totally agree with you, there is absolutely NO point in downgrading... the EFI on the 907ie might not be perfect but it is much better than any carburator setup.

While I don't much see the point of downgrading, I agree with Gert, neither the p7 or the p8 has any advantage over a good carb setup

Re: Carb convert.

Posted: Thu Oct 28, 2010 1:37 pm
by Tamburinifan
how different is a p7 to a p8?...or what are the advantages
You don`t need Additional memory board to use some chips &
it has possibility for an offset map.