Commando engine in Featherbed

cliffa · Aug 19, 2019

Rather obviously not a Commando engine, but I saw this parked in the school playground at the top of Bray Hill in 2017 during the Classic TT

It's the nicest amalgamation I've seen, and fills the frame rather nicely I think.

Cheers,

cliffa.

cliffa · Aug 19, 2019

ludwig said:
This is how I did mine :

The curved plates are 8 mm steel.
I doubt ordinary iron can take the (my) weight standing up.
The brazed on tubes are like mini isolastics, with Teflon end spacers.
The connection rod is adjustable, to set the angle of the footrests.
LH footrest is slotted for an easier installation of the rod.
The supports are bolted to the frame tubes on the existing mounting points. No drilling or welding on the frame.
The rubber buffers are over the entire length of the tubes, but quite soft.

RH footrest :

LH footrest :

LH support ( not very clear) :

Connection rod :

Now, to be honest, I took the bike on a ride today and paid special attention to the vibration. There is still some vibration coming trough, but it is low frequency and not uncomfortable at all. After a few km, I don't notice it anymore ..

Truly I-SOLE-astic !!

Matchless · Aug 19, 2019

I will concede on the Harley engined one.

grandpaul · Aug 19, 2019

baz said:
Sorry I can't agree on that one,a unit triumph engine is just too short for a feather bed, just my opinion no offense meant

No offense taken.

acotrel · Aug 19, 2019

cliffa said:
Rather obviously not a Commando engine, but I saw this parked in the school playground at the top of Bray Hill in 2017 during the Classic TT

It's the nicest amalgamation I've seen, and fills the frame rather nicely I think.

Cheers,

cliffa.

I have always liked that motor, it is the best one Harley ever made. I once rode on a circuit in Melbourne, at the same time as Don Emde on the XR750TT. He ran the timing side bearing, so could not race when it mattered. I wish I had thought about the Sportster motor when I was building the Seeley 850. The bearing problem was fixed and the later models have 5 speed boxes. However top gear in their box is an overdrive. If you used that motor, you would have to fiddle the box to make the top 4 gears close ratio. Then the bike would really fly.

grandpaul · Aug 19, 2019

ludwig said:
The original lettering was welded up and a new one engraved.
( how someone can think this is a modified Atlas cover is beyond me ..)

You yourself admit it is a modified Commando cover. In the same manner, an Atlas cover can be modified.

acotrel · Aug 19, 2019

My Seeley 850 never vibrates, but it rocks backwards and forwards when it is idling.

grandpaul · Aug 19, 2019

ludwig said:
This is how I did mine :

Wow! that sure beats the heck out of the P11's weird arrangement!

acotrel · Aug 19, 2019

Sportster motors are probably cheaper than Commando motors, and easier to get going faster.

Matt Spencer · Aug 19, 2019

Be one of the better Farmall injuns ti fit . Dunno if the F B Harleys a real F Bed , was some outfit making them ,
oversize frames to suit Harleys , as Std. is to tight . Dunno about a Inter. tho.

Matt Spencer · Aug 19, 2019

Presume this is one of them . ? pity about the brat scribbling on the picture .

Dunno specs on this , but a earlier injun Id think .

People used to chuck Matchy / AJS top ends on olde WR ? 750 H. D.s .
Desperate times call for desperate measures .
Think a Big Block Harley might work .
But with sportsters out to 1600 , youd need a 2 litre to justify it .

Matt Spencer · Aug 19, 2019

Nortons for Retards .

https://www.youtube.com/watch?v=NVT_yPK_4Pg

ashman · Aug 19, 2019

Its funny how things go off topic from the OP as it was about Commando engine in Featherbed, yes lots of motor can be used but its not what the OP was asking, I have given my account of my experience with my Commando/Featherbed and others with their experience some good some bad and then from others who have never done it before but they have their opinions on the subject, I just hope the OP hasn't been put off with the idea, like I have always said if done right a Commando/Featherbed will be one of the best looking bikes built as well super light and will blow your mind in how they handle and throw it around without much effort.
Mine isn't completely vibration free it has its moments at certin RPMs but what bike doesn't and I can ride mine comfortably all day without any problems at all, things don't fall off it, I still have all my fillings in my teeth.
Then there was no mention if race or road, just Commando engine in a Featherbed and if the vibrations are so bad I think I would have got rid of mine a long time ago, but its not I been riding it for over 38 years now and most of that time it was a everyday ride and its now showing its age but its still a great bike to ride.
Would I do it again, hell yer.

Ashley

acotrel · Aug 19, 2019

The John Trease Harley in Victoria is the big motor in a featherbed frame with a 5 speed box. It runs in the pre'62 historic class. A sportster motor in a Mk3 Seeley frame would be much better, but would run in the next period, with Commandos and 1000cc methanol-fuelled CB750s.
If you used a Sportster motor, I think getting the gearbox right might send you insane. And it would be critical if you raced the bike.

http://www.andrewsproducts.com/motorcycle-parts

acotrel · Aug 19, 2019

ashman said:
Its funny how things go off topic from the OP as it was about Commando engine in Featherbed, yes lots of motor can be used but its not what the OP was asking, I have given my account of my experience with my Commando/Featherbed and others with their experience some good some bad and then from others who have never done it before but they have their opinions on the subject, I just hope the OP hasn't been put off with the idea, like I have always said if done right a Commando/Featherbed will be one of the best looking bikes built as well super light and will blow your mind in how they handle and throw it around without much effort.
Mine isn't completely vibration free it has its moments at certin RPMs but what bike doesn't and I can ride mine comfortably all day without any problems at all, things don't fall off it, I still have all my fillings in my teeth.
Then there was no mention if race or road, just Commando engine in a Featherbed and if the vibrations are so bad I think I would have got rid of mine a long time ago, but its not I been riding it for over 38 years now and most of that time it was a everyday ride and its now showing its age but its still a great bike to ride.
Would I do it again, hell yer.

Ashley

It depends on what you want. There is nothing authentic about a Commando engine in a featherbed frame. If you are building a bitsa, you might as well go for performance and handling excellence.

acotrel · Aug 19, 2019

I would like an DOHC Jaguar engine in a MK4 Jaguar with a Tremac CR gearbox. However I don't know why. I know what you are saying - some things are just good, because they are. I had to laugh at one of our car guys, he built a 1969 Ford Mustang with all the modern V8 supercar stuff underneath. When he got pinged, he simply built another one which actually complied and raced that. I really love a good cheater. Racing is racing - historic racing is bullshit, if even one person cheats. But in Australia the only bike development classes are historic. I absolutely love Goodwood Revival and the Lansdowne Series.
They are real racing. Perhaps they should be a combined effort ?

I have a friend who builds replica Ford Daytona cars with Chev engines and Tremac boxes. He seems to sell a few, but I don't know who buys them. Same with one of our local guys who recently moved to Queensland - he builds Ford GT40s and sells them. It is only at very unusual race meetings that you could race any of them.

jseng1 · Aug 19, 2019

grandpaul said:
I agree... Smooth as silk

Yes the Triumph mill is smoother than a 89mm stroke Commando motor with stock pistons and rods but not as smooth as a short stroke Norton 750 with the right aftermarket pistons and rods. The high domed Triumph pistons can never match the low weight of lighter (lightweight with raised pin) flat top Norton pistons. The Triumph rods are either 6" (short rod) or 6.5" (long rod) long where the aftermarket rods (for a short stroke Nort) can be over 6.5" long and that makes for a smoother running motor. And in the end the short stroke Norton 750 can also make more power than the Triumph 750 as proven by Ron Wood. I'll take the Norton motor (with the right components) over the Triumph any day. The Triumph may be pretty and I might prefer the Triumph if I was a Triumph nut, but I'm not.

Top off your Featherbed Nort with a belt drive, a trim alloy primary cover and you're set.

Fast Eddie · Aug 20, 2019

grandpaul said:
You yourself admit it is a modified Commando cover. In the same manner, an Atlas cover can be modified.

The Atlas cover did not have the Norton logo machined into it. Moreover, it did not have the points housing. You’re right in saying one ‘could’ be modified, but putting a points housing on would be a big job. And a rather futile one seeing as (most) Commando covers come with them as stock.

ashman · Aug 20, 2019

acotrel said:
It depends on what you want. There is nothing authentic about a Commando engine in a featherbed frame. If you are building a bitsa, you might as well go for performance and handling excellence.

Mine might be a bitsa but its all Norton and it performs great and the handling is excellent.

Danno · Aug 20, 2019

I have to wonder why more Featherlastics weren't put together. The one in the lineup at the 50th Anniversary of the Commando show at Barber looked great. It appears to be a pretty simple build. Here's another;

Commando engine in Featherbed

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