Can I fit an ES2 engine in an old Bolt up Dommie frame.

No Keith is the answer. you don't want to read.  The front engine plate mounting lugs are different and there is a flattened part of the top right-hand tube to allow clearance of the rocker box.  Far better to do a swap with someone with a wideline single frame.  They are rarer than the Dommie frame however.  Good luck, Howard

Hello  well if you have a  1952 to 1954 Model 88 frame  then the way of fitting a big single in there is  one  you need to take all the paint of  then with some help  heat up the right-hand top tube  and with a nice piece of thick flat bar with now glowing hot  put the flat bar on the inside os the top tube and nip it up with a number of G clamps  you only need about a good Half inch flat ,  then try sitting the engine in place and with some cardboard  make  some cut-outs  for the engine plates  out of 8mm alloy its best to have cut by laser or high presser water cutting  once you have this done it just a case of  getting some nice  stainless studs and nuts and washers  and fixing the engine in place  or finding  some  Featherbed  engine plate for a Singel,    happy engineering   Yours  Anna J    

Hi Keith,

   If you have a pre featherbed engine, you might have to make engine plates to mount the mag-dyno.

The frame rail was left alone for this project.

I think there is a tad more clearance on the bolt up frames for the tappet adjustment, but you will have to modify the engine plates to fit a magdyno. The picture shows a Model19 in bolt up frame but that needed the bottom of the tank modified to give clearance for the rocker box and a modified head steady.

Paul

A very tidy piece of engineering.......well done!!!

My current project has similar issues with fitting all the important chunks snugly inside a frame. My worry being.......does the mag/dyno not get cooked on long journeys???

See attachment please.

Norton fitted a 1948 pattern 16H engine experimentally into a bolt-up Featherbed There may be some clues in the way that they did it.

Original Norton frames are so hard to find these days that I now consider it a bit unnecessary to alter them at all ....why not find an engine/gearbox combination that fits your frame that might 'only' need some bespoke engine plates being made? 

I have a 'cafe racer' Domi 99 that was once a 'Delux' but never have I felt I should grind off the original panel fitting lugs on the frame. It's much better in its factory form I feel. Maybe in the future someone rebuilds it as a Delux (not me!).