![Bimota Forum Forum Index](templates/BimotaForum/images/logo_phpBB.gif) |
Bimota Forum Forum for Bimota Owners and Riders
|
View previous topic :: View next topic |
Author |
Message |
coops
Joined: 19 Apr 2021 Posts: 12 Location: New Zealand
|
Posted: Fri Jul 16, 2021 8:59 am Post subject: Furano Tuning’s |
|
|
Hi. New Furano owner. I haven’t ridden the bike yet but I believe it was running OK and sounds good. I am sorting the bike for first registration in my country. But I do know that it’s been running rich by the deposits in the exhaust system. I really want to work with what I have and keep the bike as original as possible so while it’s in bits ......
Not going to go into to much details just now but I have fitted an adjustable fuel pressure regulator to give me some tune ability.
After testing all the sensors, which do all work, but air box sensor is reading about 5 degrees C cold.
My question here.....Has anyone tried fitting a resistor or resisting pot in temp sensor to fool the ECU and lean the fueling?
Because this is what I’m considering doing.
Once I have sorted this bike (injection system) and I will.
I will give my opinion or best options for Furano owners to fix or improve fueling . As I know there is naff all info out there about sorting them.
Cheers Steve _________________ Bimota Furano
Kawasaki H1
Kawasaki H1 race
FZR1000 race
Ducati 750ss race |
|
Back to top |
|
![](templates/BimotaForum/images/spacer.gif) |
Jonny B Bad
Joined: 05 Dec 2009 Posts: 555 Location: NE London
|
Posted: Sat Jul 17, 2021 8:44 am Post subject: Furano fuelling |
|
|
That’s very public spirited Steve. I’ve been wrestling with the carb version YB8 for years, which came out of Rimini hopelessly rich, with the same carb set-up as the 1989 FZR1000, which was too rich even for the Yamaha (changed in 1990) never mind the completely different induction on the Bimota. What I have learned is that this motor is far more intolerant of poor fuelling set-up than other big bore bikes of the day, such as the GSXR11.
Good luck - there are definitely others who will be interested in the results of your endeavours. _________________ What, Jonny's gone! |
|
Back to top |
|
![](templates/BimotaForum/images/spacer.gif) |
coops
Joined: 19 Apr 2021 Posts: 12 Location: New Zealand
|
Posted: Sun Jul 18, 2021 7:28 am Post subject: |
|
|
Interesting.
I also own a 89 fzr1000 and had it dyno tuned after doing some minor changes and the fueling was pretty good. Had to drop mains one size.
( I live at sea level)
It’s fairly normal for manufacturers to over fuel bikes for different countries/ fuel and elevations. Safety factors. Better rich than lean.
But Bimota got it slightly wrong in this case
Pity they didn’t just put 3 adjustable pots one the back of the ECU instead of one.
No worries I’ll sort it. _________________ Bimota Furano
Kawasaki H1
Kawasaki H1 race
FZR1000 race
Ducati 750ss race |
|
Back to top |
|
![](templates/BimotaForum/images/spacer.gif) |
Andrew034
Joined: 02 Apr 2017 Posts: 52 Location: Sydney
|
Posted: Tue Jul 20, 2021 5:22 am Post subject: |
|
|
I'm interested in your findings.
For your question, back in the day applying a resistor to modify a sensor output was a common tuning trick (normally we'd trick the temperature readings lower to make the engine richer for more power at the track).
When I bought my Furano 4 years ago I spent huge energy and time trying to interrogate the fuel injection (and got nowhere). My driver was I also though the bike was running rich, because when I ran it when I got it (and before I rode it) my eyes would water from the exhaust fumes.
However, I'll list some of my findings here:
1. TPS - the ECU is a modified P7 (IAW041) and uses a Colvern CP17/707 TPS, my bike runs best when the TPS is reading 650mV at idle (it is not identical to a Ducati or Moto Guzzi system - which is 150mV fully closed). A conversation with local older tuners noted the Mebber Marelli P7 would read the TPS on power-up and assume this was the idle setting. Further I've not attempted to determine the actual throttle angle at idle (it should be 2.5 degrees if it is identical to other Webber Marelli settings).
2. The ECU won't talk to software - you can make a "flashing light: error reader - I found this useless. As an aside, the P7 can talk to software with the correct EPROM and it was suggested I install a Moto Guzzi unit to interrogate the ECU (not to run the bike), then reinstall the Bimota EPROM to run the engine (I never tried this) - software would allow me to determine what the ECU was actually seeing from the sensors.
3. Fuel pressure is 3 bar (measured) on my bike when running.
4. The ECU only appears to control the Fuel Injectors, I believe the ignition is still controlled by the Yamaha igniter (that also operates the EXUP).
I don't have a CO reader, so I've never attempted to adjust the trimmer (but this is an easy way to lean the engine). I have always thought it is slightly rich (at idle) - especially as it will start and run smoothly on a sunny morning in winter (say 10 - 12 degrees celcius air temperature) without the hand throttle.
Notwithstanding, after a couple of years, I came to the conclusion the bike is OK, basically it runs well, returns about 7 litres / 100 km fuel consumption (which similar to my other bikes). So I stopped worrying.
My bike has had the injectors replaced in the past (I have a receipt in the history file).
So in summary, I think they do run rich at idle but when the throttle is opened, the fuelling is pretty good.
Let me know about your findings.
Andrew... |
|
Back to top |
|
![](templates/BimotaForum/images/spacer.gif) |
coops
Joined: 19 Apr 2021 Posts: 12 Location: New Zealand
|
Posted: Tue Jul 20, 2021 10:10 am Post subject: |
|
|
Thanks for the info Andrew. Much appreciated
I will get back here in a month or two with my findings.
Cheers Steve _________________ Bimota Furano
Kawasaki H1
Kawasaki H1 race
FZR1000 race
Ducati 750ss race |
|
Back to top |
|
![](templates/BimotaForum/images/spacer.gif) |
ZiporaTilda
Joined: 21 Sep 2021 Posts: 1
|
Posted: Tue Sep 21, 2021 1:45 pm Post subject: |
|
|
That one is quite helpful!
One not to be forgotten |
|
Back to top |
|
![](templates/BimotaForum/images/spacer.gif) |
coops
Joined: 19 Apr 2021 Posts: 12 Location: New Zealand
|
Posted: Thu Nov 11, 2021 3:31 am Post subject: |
|
|
So, ive had it on the Dyno (one of the best dyno tuners in the country)
I took it in completely standard including the TPS set at factory .65V
The fueling is OK. Not great, not bad, but acceptable. to generalize......
Idle very good, didnt need adjustment
1/4 throttle run is a bit rich
1/2 throttle a bit rich
3/4 throttle a bit lean
full throttle very good
slight lean spot when cracking throttle but nothing major.
Unfortunate about slight lean condition at 3/4 which meant we couldnt make a correction with resistor pot i added to intake sensor. so i took it away without adjustments. So that was good.
The power curve was excellent, like all exup engines except my Furano
has 11-17 more hp than a stock Yamaha. Which was very surprising.
So Bimotas claims arent ridiculous at all!
So there we go. Nothing wrong with this Furanos injection.
Also it starts and idles much better than my carbed 1000.
Steve _________________ Bimota Furano
Kawasaki H1
Kawasaki H1 race
FZR1000 race
Ducati 750ss race |
|
Back to top |
|
![](templates/BimotaForum/images/spacer.gif) |
Andrew034
Joined: 02 Apr 2017 Posts: 52 Location: Sydney
|
Posted: Mon Dec 13, 2021 1:59 am Post subject: |
|
|
Good to see the results, thanks. And I'm happy to see the 650mV TPS value seems to be about right.
I know from track day experience the Furano makes good power (its way faster than contemporaries of the era) and Bimota claimed a big number too, but 17hp is amazing.
On that note, I've always considered the bike would make more power as the original FZR carburettors are 28mm (I think) and the Bimota throttle-bodies are 48mm so there is a huge increase in intake breathing capacity (and the fuel injection is really needed for fuel atomisation at low speeds so the bike will run cleanly).
The exhaust on the other hand is standard Yamaha up to the EXUP, the muffler is something else, I suspect it is a standard Yamaha unit covered by a fancy carbon cylinder (I recently had the end cap fall off mine, while making a new end cap, I discovered under the carbon wrapping is a heavy OEM style aluminium silencer with a small outlet and convoluted internals. So I'd say the end can is the factory supplied restriction that limits power and a new end can may release even more (not that the bike needs it).
After that more power would likely require surgery, maybe elimination of the EXUP blah blah blah...
Andrew... |
|
Back to top |
|
![](templates/BimotaForum/images/spacer.gif) |
Jonny B Bad
Joined: 05 Dec 2009 Posts: 555 Location: NE London
|
Posted: Mon Dec 13, 2021 11:16 am Post subject: Furano fuelling |
|
|
The air box of the FZR1000, having to sit on top of downdraught carbs and under the tank, had a limited ability to provide air to the motor. The exup valve, what ever the claims made for it, impedes gas flow as well. The Bimota air box has the ability to deliver more air (with the right filter) than the FZR one. But there’s not much point making that mod, unless you also eliminate the restriction on the other side of the motor, i.e. the exup valve - after market headers are the way to go, as the originals are still restrictive without the valve.
The received wisdom that an FZR cannot be made to work properly without the exup, may well be right, because there’s not much to be done with the air box/filter, other than ditching it for pods, where getting broadly equal flow to all four is difficult/impossible. But the Bimota air box does allow for a bigger filter giving much better flow. So ditching the exup valve is possible. It needs a lot of perseverance to get the jetting of the carbs right, unless you’ve got access to a dyno that nobody else wants to use. But the end result is a bike that works well throughout the rev range and judging by the larger pilots, needle jets and mains, is stronger than the original configuration. I’m not going to make claims for peak power, as that would only be relevant for comparison to another bike on the same dyno, but it feels a quicker, crisper bike on the road. Albeit that’s not difficult, because a carb’d YB is a soggy mess out of the crate, because the air filter was deliberately kept small, so that they could keep the exup exhaust system and once the needle jets start to wear, in a matter of a few hundred miles, it’s over-fuelling all the way from idle to when the mains kick in. _________________ What, Jonny's gone! |
|
Back to top |
|
![](templates/BimotaForum/images/spacer.gif) |
|
|
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum
|
Powered by phpBB © 2001, 2005 phpBB Group
The Bimota Forum has no official connection to Bimota S.p.A.. We just ride or are interested in their motorcycles and support the brand. All trademarks are acknowledged
|