brook.reams
B Reams
1983 R100RS Install Engine Top End
The engine came with the stock 8.2:1 compression pistons. But the early RS motors came with high compression 9.5:1 pistons. The bike has 83,000+ miles on it. So I decided to install new high compression pistons. <a href="http://www.rubberchickenracinggarage.com" target="_blank" rel="noopener noreferrer">Tom Cutter at Rubber Chicken Racing Garage</a>, told me due to the very tight piston clearances in the Nikasil cylinders and the amount of variation in piston diameter with the new pistons, the best way to proceed is to replate the cylinders with Nikasil and hone them to match the pistons to ensure proper clearance. So, I send him the new pistons, rings, wrist pins and old cylinders for this work to be done. I also had him vapor hone the cylinders to refinish them to the factory patina.
<a title="New SS Push Rod Tubes & Original Head Studs Installed" href="https://www.flickr.com/photos/brook-reams/49581368346/in/album-72157713244736881/" target="_blank" rel="noopener noreferrer" data-flickr-embed="true"><img src="https://live.staticflickr.com/65535/49581368346_e099c763ca_c.jpg" alt="Refinished Cylinders with New Push Rod Tubes" width="800" height="600" /></a>
Refinished Cylinders with New Push Rod Tubes
The other work needed was to the heads. When I tested them, the valves were leaking. So I sent the heads to Randy Long, at Long's Mechanical Services, who is a well respected head rebuilder, for his opinion. We decided to replace the exhaust valves, all the exhaust guides, springs and keepers. I had him machine the heads for dual plugs. I have dual plug heads on two airhead bikes and I like the improved gas mileage. Randy milled the valve cover mating surfaces so they are flat and bead blasted the heads so they look brand new.
<a title="Rebuilt Heads-I Had Them Dual Plugged" href="https://www.flickr.com/photos/brook-reams/49611874891/in/album-72157713339451047/" target="_blank" rel="noopener noreferrer" data-flickr-embed="true"><img src="https://live.staticflickr.com/65535/49611874891_8891464244_c.jpg" alt="Randy Long's Rebuilt Heads" width="800" height="600" /></a>
Randy Long's Rebuilt Heads
<a title="Rebuilt Head with New Exhaust Valve" href="https://www.flickr.com/photos/brook-reams/49611357718/in/album-72157713339451047/" target="_blank" rel="noopener noreferrer" data-flickr-embed="true"><img src="https://live.staticflickr.com/65535/49611357718_84174d481d_c.jpg" alt="Rebuilt Head with New Exhaust Valve and Dual Plug Conversion" width="800" height="600" /></a>
Rebuilt Head with New Exhaust Valve and Dual Plug Conversion (Note Two Spark Plug Holes)
Here is what I ended up with. The red tape indicates things I need to do before first engine start: install new spark plugs and put oil in the engine. The rags protect the heads from getting anything inside from the intake and exhaust ports.
<a title="Red Tape Means Not Ready Yet" href="https://www.flickr.com/photos/brook-reams/49612127297/in/album-72157713339451047/" data-flickr-embed="true"><img src="https://live.staticflickr.com/65535/49612127297_488b9ec348_c.jpg" alt="Red Tape Means Not Ready Yet" width="800" height="600" /></a>
Red Tape Means Not Ready Yet
<a title="All Done" href="https://www.flickr.com/photos/brook-reams/49611870581/in/album-72157713339451047/" data-flickr-embed="true"><img src="https://live.staticflickr.com/65535/49611870581_3a20ae81dc_c.jpg" alt="All Done" width="800" height="600" /></a>
All Done
Here is written documentation of the procedure:
<ul>
<li><a href="https://brook.reams.me/bmw-motorcycle-rebuilds/1983-bmw-r100rs-rebuild-project-index/11-bmw-1983-r100rs-install-top-end/">11 BMW 1983 R100RS Install Top End</a></li>
</ul>And here is a video of the procedure.
<strong>VIDEO: <em><span style="text-decoration: underline;">1983 BMW R100RS Install Engine Top End</span></em></strong>
The engine came with the stock 8.2:1 compression pistons. But the early RS motors came with high compression 9.5:1 pistons. The bike has 83,000+ miles on it. So I decided to install new high compression pistons. <a href="http://www.rubberchickenracinggarage.com" target="_blank" rel="noopener noreferrer">Tom Cutter at Rubber Chicken Racing Garage</a>, told me due to the very tight piston clearances in the Nikasil cylinders and the amount of variation in piston diameter with the new pistons, the best way to proceed is to replate the cylinders with Nikasil and hone them to match the pistons to ensure proper clearance. So, I send him the new pistons, rings, wrist pins and old cylinders for this work to be done. I also had him vapor hone the cylinders to refinish them to the factory patina.
<a title="New SS Push Rod Tubes & Original Head Studs Installed" href="https://www.flickr.com/photos/brook-reams/49581368346/in/album-72157713244736881/" target="_blank" rel="noopener noreferrer" data-flickr-embed="true"><img src="https://live.staticflickr.com/65535/49581368346_e099c763ca_c.jpg" alt="Refinished Cylinders with New Push Rod Tubes" width="800" height="600" /></a>
Refinished Cylinders with New Push Rod Tubes
The other work needed was to the heads. When I tested them, the valves were leaking. So I sent the heads to Randy Long, at Long's Mechanical Services, who is a well respected head rebuilder, for his opinion. We decided to replace the exhaust valves, all the exhaust guides, springs and keepers. I had him machine the heads for dual plugs. I have dual plug heads on two airhead bikes and I like the improved gas mileage. Randy milled the valve cover mating surfaces so they are flat and bead blasted the heads so they look brand new.
<a title="Rebuilt Heads-I Had Them Dual Plugged" href="https://www.flickr.com/photos/brook-reams/49611874891/in/album-72157713339451047/" target="_blank" rel="noopener noreferrer" data-flickr-embed="true"><img src="https://live.staticflickr.com/65535/49611874891_8891464244_c.jpg" alt="Randy Long's Rebuilt Heads" width="800" height="600" /></a>
Randy Long's Rebuilt Heads
<a title="Rebuilt Head with New Exhaust Valve" href="https://www.flickr.com/photos/brook-reams/49611357718/in/album-72157713339451047/" target="_blank" rel="noopener noreferrer" data-flickr-embed="true"><img src="https://live.staticflickr.com/65535/49611357718_84174d481d_c.jpg" alt="Rebuilt Head with New Exhaust Valve and Dual Plug Conversion" width="800" height="600" /></a>
Rebuilt Head with New Exhaust Valve and Dual Plug Conversion (Note Two Spark Plug Holes)
Here is what I ended up with. The red tape indicates things I need to do before first engine start: install new spark plugs and put oil in the engine. The rags protect the heads from getting anything inside from the intake and exhaust ports.
<a title="Red Tape Means Not Ready Yet" href="https://www.flickr.com/photos/brook-reams/49612127297/in/album-72157713339451047/" data-flickr-embed="true"><img src="https://live.staticflickr.com/65535/49612127297_488b9ec348_c.jpg" alt="Red Tape Means Not Ready Yet" width="800" height="600" /></a>
Red Tape Means Not Ready Yet
<a title="All Done" href="https://www.flickr.com/photos/brook-reams/49611870581/in/album-72157713339451047/" data-flickr-embed="true"><img src="https://live.staticflickr.com/65535/49611870581_3a20ae81dc_c.jpg" alt="All Done" width="800" height="600" /></a>
All Done
Here is written documentation of the procedure:
<ul>
<li><a href="https://brook.reams.me/bmw-motorcycle-rebuilds/1983-bmw-r100rs-rebuild-project-index/11-bmw-1983-r100rs-install-top-end/">11 BMW 1983 R100RS Install Top End</a></li>
</ul>And here is a video of the procedure.
<strong>VIDEO: <em><span style="text-decoration: underline;">1983 BMW R100RS Install Engine Top End</span></em></strong>