Building Sidecar Motor
I started collecting parts for this motor a while ago and then got side tracked building the two-stroke outfit.
This is not intended to be a how to build a motor it is more of a show and tell what I have done to build a race motor for a sidecar. Most of what is shown is not necessary on solos and certainly a waste of effort on a road bike. Having said that you can take a motor straight out of a bike and throw it in a sidecar and have great fun, its just as you start to go faster and tune your motor more problems start to arise. I have also included some stuff about fuel pumps and batteries.
This did not start as a complete motor it is made up from parts boxes, all the parts were cleaned before assembly. I have a bead blaster and homemade vapour blaster still the cleaning and looking for missing parts took a lot of time. I have also zinc plated most of the XS special hardware that was looking a bit tatty.
Parts Sources:
Apart from the normal XS parts used other specialist parts were sourced from the following:
Smed Speed UK
http://www.smedspeed.co.uk/
880 Pistons, copper base and head gaskets and a used Euro 533 crank. Howard kindly disassembled the crank to save shipping weight. The busines has changes hands and Howard is no longer at Smed speed but they are well worth a look if you want performance parts.
Westwood Liners.
https://westwoodcylinderliners.co.uk/
Westwood manufacture the liners to Howard’s specification. Howard generously arranged for me to purchase the liners direct from Westwood. Talk to Smed speed about liners.
Heiden Tuning
https://www.heidentuning.com/
533 Con Rod kits, big bore cylinders without sleeves. 8 plate clutch kit, clutch hub spring kit.
650 Central
https://www.650central.com/
Lillie Replica head
Sources of information
Smed speed http://www.smedspeed.co.uk/tech.html#880_anc
XS 650 Club of Australia https://old.xs650.org.au/Club Racer Stuff/Club Racer.htm
XS650.com these pages from Jim and Hotdog https://www.xs650.com/threads/xs650-top-end-buildup.52041/ https://www.xs650.com/threads/long-rod-pistons.23581/page-5
To give you background on to what is needed to be done read through the how to on Smed Speeds website.
As a refresher have a look at Jim’s excellent top end rebuild how to in the tech section.
The gearbox mods are also detailed on Smed speeds web site.
Lot of good info from Hotdog on his thread about making go fast parts.
Putting it all together
Cleaning the cases, remove the starter post. Blast media can get in a manufacturing pocket behind the post and is a pain to clean it out. To remove the starter post prop the case on its side with the post facing down in a barbeque or oven. Heat the case and eventually the case will expand enough, and the post will fall out.
Installing the post again is the reverse you heat the case and cool the post. Make a simple guide to ensure the retaining screw hole is aligned.
The studs were pulled using two nuts tightened against each other and a lot of heat (MAP gas) on the cases around the stud bosses. Measure and record the heights and locations of all studs before you start.
All the threads were filled with old bolts and the cases were vapour blasted. Glass beads will lock a thread better and faster than any Loctite product.
Strengthen cases
The cases had external and internal strengthening welded in place.
The area under the upper rear mount had a plate welded to it to make to a diaphragm. Significant internal cross braces were welded in place and the lower rear mount was strengthened by an external plate bent round the existing mount. These are where cracks happened in the past.
After this the cases were then taken to a specialist machine shop to be shot peened and have the throats bored to take the 880 liners from memory 91mm.
The con rods and clutch basket were also shot peened to increase strength.
On return the cases were scrubbed in hot soapy water. Then an oil dead spot in the lower case was filled with epoxy putty. If the case cracks in this area it is impossible to weld so the epoxy may help keep the case oil tight.
The front oil gallery plug was removed, and all the oil ways were cleaned. It was a shock what came out of the front oil passage. After drying (there is a ferrous tube in the case) the gallery was replunged.
The cases were Scrubbed again and the starter post reinstalled.
I dont know the size limit per post so will stop here and start another.
I started collecting parts for this motor a while ago and then got side tracked building the two-stroke outfit.
This is not intended to be a how to build a motor it is more of a show and tell what I have done to build a race motor for a sidecar. Most of what is shown is not necessary on solos and certainly a waste of effort on a road bike. Having said that you can take a motor straight out of a bike and throw it in a sidecar and have great fun, its just as you start to go faster and tune your motor more problems start to arise. I have also included some stuff about fuel pumps and batteries.
This did not start as a complete motor it is made up from parts boxes, all the parts were cleaned before assembly. I have a bead blaster and homemade vapour blaster still the cleaning and looking for missing parts took a lot of time. I have also zinc plated most of the XS special hardware that was looking a bit tatty.
Parts Sources:
Apart from the normal XS parts used other specialist parts were sourced from the following:
Smed Speed UK
http://www.smedspeed.co.uk/
880 Pistons, copper base and head gaskets and a used Euro 533 crank. Howard kindly disassembled the crank to save shipping weight. The busines has changes hands and Howard is no longer at Smed speed but they are well worth a look if you want performance parts.
Westwood Liners.
https://westwoodcylinderliners.co.uk/
Westwood manufacture the liners to Howard’s specification. Howard generously arranged for me to purchase the liners direct from Westwood. Talk to Smed speed about liners.
Heiden Tuning
https://www.heidentuning.com/
533 Con Rod kits, big bore cylinders without sleeves. 8 plate clutch kit, clutch hub spring kit.
650 Central
https://www.650central.com/
Lillie Replica head
Sources of information
Smed speed http://www.smedspeed.co.uk/tech.html#880_anc
XS 650 Club of Australia https://old.xs650.org.au/Club Racer Stuff/Club Racer.htm
XS650.com these pages from Jim and Hotdog https://www.xs650.com/threads/xs650-top-end-buildup.52041/ https://www.xs650.com/threads/long-rod-pistons.23581/page-5
To give you background on to what is needed to be done read through the how to on Smed Speeds website.
As a refresher have a look at Jim’s excellent top end rebuild how to in the tech section.
The gearbox mods are also detailed on Smed speeds web site.
Lot of good info from Hotdog on his thread about making go fast parts.
Putting it all together
Cleaning the cases, remove the starter post. Blast media can get in a manufacturing pocket behind the post and is a pain to clean it out. To remove the starter post prop the case on its side with the post facing down in a barbeque or oven. Heat the case and eventually the case will expand enough, and the post will fall out.
Installing the post again is the reverse you heat the case and cool the post. Make a simple guide to ensure the retaining screw hole is aligned.
The studs were pulled using two nuts tightened against each other and a lot of heat (MAP gas) on the cases around the stud bosses. Measure and record the heights and locations of all studs before you start.
All the threads were filled with old bolts and the cases were vapour blasted. Glass beads will lock a thread better and faster than any Loctite product.
Strengthen cases
The cases had external and internal strengthening welded in place.
The area under the upper rear mount had a plate welded to it to make to a diaphragm. Significant internal cross braces were welded in place and the lower rear mount was strengthened by an external plate bent round the existing mount. These are where cracks happened in the past.
After this the cases were then taken to a specialist machine shop to be shot peened and have the throats bored to take the 880 liners from memory 91mm.
The con rods and clutch basket were also shot peened to increase strength.
On return the cases were scrubbed in hot soapy water. Then an oil dead spot in the lower case was filled with epoxy putty. If the case cracks in this area it is impossible to weld so the epoxy may help keep the case oil tight.
The front oil gallery plug was removed, and all the oil ways were cleaned. It was a shock what came out of the front oil passage. After drying (there is a ferrous tube in the case) the gallery was replunged.
The cases were Scrubbed again and the starter post reinstalled.
I dont know the size limit per post so will stop here and start another.