920cc with 270 crank

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Fast Eddie said:
I’m not sure about this... but I’m gonna go out on a limb here...

I kinda suspect that if the OP wanted a stock Commando, then he would have, well, you know... bought a stock Commando...!! :rolleyes:

HanaAna, don’t listen to this lot, those old farts that are telling you to ‘go standard‘ are running a methanol burning Seeley and a totally none standard hot rod P11 FFS !

keep on keeping on...
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Don’t worry, I’m not giving up. Totally agree, and if I wanted STD Commando I would have bought one also ;-D
 
Maybe something got lost in translation.

I never said stock, or STD.

If you think you are going to make a "drivable" street bike with what you have by just changing the 270 crank to a 360 crank, more power to you. I doubt it will be that easy with that head or fuel delivery system.

I do all kinds of things because I can. Some work, some don't.
 
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Schwany said:
Maybe something got lost in translation.

I never said stock, or STD.

If you think you are going to make a "drivable" street bike with what you have by just changing the 270 crank to a 360 crank, more power to you. I doubt it will be that easy with that head or fuel delivery system.

I do all kinds of things because I can. Some work, some don't.
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What do you find problematic with the head? Or the fueling system? I've been riding with the bike for two summers now and it was very drivable, EXCEPT for the Vibrations on rpm below 3.5k.
 
HanaAna said:
The reason I want 360 crank is because, since I'm not racing, I want to make this bike more driveable on the street. On open roads this setup was really nice but obviously the shakes were quite disturbing on lower revs in the city (< 3500 rpm). 270 flywheel weight was 8.44 lb. I have flywheel that I think is the original, weight 11 lb.
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My misinterpretation. I interpreted your desire to make the bike more driveable on the street as it wasn't running that well at lower RPMs. I also thought (because of reading things on the internet, which may or may not have been true) 270 cranks were smoother running than 360 cranks.
HanaAna said:
What do you find problematic with the head? Or the fueling system? I've been riding with the bike for two summers now and it was very drivable, EXCEPT for the Vibrations on rpm below 3.5k.
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I think if you think changing out the crank is all that needs to be done, that is what should be done.

If the bike shakes disturbingly at lower RPMs after swapping out the crank, you'll know why I mentioned the head and fuel delivery system. The motor obviously wasn't built to be a street bike, and ridden at low speed. It's an interesting complicated racing design project.

If it runs great after swapping out the crank, I'm just another old fart on the interweb with my dumbassness showing. ;)
 
Schwany said:
My misinterpretation. I interpreted your desire to make the bike more driveable on the street as it wasn't running that well at lower RPMs. I also thought (because of reading things on the internet, which may or may not have been true) 270 cranks were smoother running than 360 cranks.

I think if you think changing out the crank is all that needs to be done, that is what should be done.

If the bike shakes disturbingly at lower RPMs after swapping out the crank, you'll know why I mentioned the head and fuel delivery system. The motor obviously wasn't built to be a street bike, and ridden at low speed. It's an interesting complicated racing design project.

If it runs great after swapping out the crank, I'm just another old fart on the interweb with my dumbassness showing. ;)
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No harm done. The fact, that I’m not native English speaker can make it hard to follow what I’m trying to say...

Most certainly this project is far from ready. Let’s say that 360 is next test.

I’m under the impression that 270 is smoother in higher revs but lower revs can be problem, isolastics for one reason. All newer bikes with 270 crank have balance shaft to handle this.

Hard to say how this thing will go, after first test drive will be wiser. To live and learn ;-D

Btw I saw your P11 on another thread, looks great! I bet that bike is a real beast!
 
Schwany said:
What does the rest of the Commando this engine came out of look like?

Yeah, getting another Commando would be the fastest route to a streetable motorcycle.
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This is how it started. Couldn't find pic from last summer... Rear end/seat will be from alloy cafe racer style this winter. Front mud guard is already aluminium and handlebars cafe-stylish.

 
Thanks for understanding how far off track I can get.

That is a beautiful one off bike. Really nice

What software are you using for the EFI?
 
HanaAna said:
Thanks! Ecu is Microsquirt and I use Tunerstudio for tuning. It has auto tuning which is really good. It’s too easy to use ;-) Tuning carburettors is sooo much more difficult!
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I have heard of Megasquirt, and Microsquirt, but only in reference to DIY automotive EFI.

Tuning EFI with software sure is a lot easier than screwing around with jets, needles, and slides.

Does the current 270 degree crank setup use timing control and sequential firing injection? I'm thinking the ignition trigger will have to change with both pistons going up and down at the same time, and you might have to use batch firing injection to simplify things. I don't really know though. My only experience with installing and tuning retrofit EFI is with small block Chevy. My gas hog.

920cc with 270 crank
 
I like your machine and I'll be damned, but the thought of finding another Commando for riding until the vibe issues can be conquered on that little screamer would be most tempting...... It could become an obsession if I were in your place.
 
Schwany said:
I have heard of Megasquirt, and Microsquirt, but only in reference to DIY automotive EFI.

Tuning EFI with software sure is a lot easier than screwing around with jets, needles, and slides.

Does the current 270 degree crank setup use timing control and sequential firing injection? I'm thinking the ignition trigger will have to change with both pistons going up and down at the same time, and you might have to use batch firing injection to simplify things. I don't really know though. My only experience with installing and tuning retrofit EFI is with small block Chevy. My gas hog.
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Sequential injection not enabled yet. I want to try it at some point. I have missing teeth plate on the crank and cam sensor for syncing. With 270 ecu calculates correct timing for the first cylinder when we know the offset and then the second cylinder will have spark after 450 degrees. 360 is quite basic with crank sensor, I've done it with Yamaha XS650 and my Triumph NRE.
 
fiatfan said:
Is the bike and engine originally built in Finland?
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Yes. Older gentleman who passed away few years back. When he started with this bike back in the 70's it was 650SS. After that the frame was changed to finnish build chrome moly wideline "copy". Gearbox from Commando and engine blocks from somewhere. It has had multiple different setups during the last 20 yrs. I'm in contact with PO's friends and the gentleman who did the more challenging block weldings and lots of other stuff, so I've been able to hear some stories. I really look up to these gentleman. One setup was homemade watercooled cylinder with the other OHC head from Yamaha V-Max. And naturally self-made crank! That setup never made to the street use because after third dyno run, engine plates gave up....
Can you imagine what kind of world of engines there are outside internet :D
 
HanaAna said:
Yes. Older gentleman who passed away few years back. When he started with this bike back in the 70's it was 650SS. After that the frame was changed to finnish build chrome moly wideline "copy". Gearbox from Commando and engine blocks from somewhere. It has had multiple different setups during the last 20 yrs. I'm in contact with PO's friends and the gentleman who did the more challenging block weldings and lots of other stuff, so I've been able to hear some stories. I really look up to these gentleman. One setup was homemade watercooled cylinder with the other OHC head from Yamaha V-Max. And naturally self-made crank! That setup never made to the street use because after third dyno run, engine plates gave up....
Can you imagine what kind of world of engines there are outside internet :D
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Wow, I posted a pic of that V-Max head engine here just a while back, in a thread about a British made 8-valve DOHC head for the Commando called Merlin. As you say, there´s all kinds of strange things going on in sheds around the world....I was thinking about the weldings, among lots of other things on your engine, not everyone would accept that challenge to weld on these old porous and oil drenched aluminium parts, it´s impressive to see all that has been done.
 
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