When it comes to building bikes, the one thing everyone seems to agree on is that they need to be better than stock. These days, with all the bolt-on parts out on the market, trying to get them to look different is a task in itself. In the last part of my build, I installed the new BDL 2-inch open beltdrive, along with the new custom belt covers that BDL offered, but the backing plate was heavy and bulky. I've seen a few that have been cut down and look great, with about 30 percent shaved off the backing plate without jeopardizing strength and functionality. I just wanted to clean up the primary area so that it looks as if there isn't even a backing plate there. It's not as if I plan to race the bike (OK, maybe just once to beat Greg), so for me the issue isn't the weight, but the look. I called BDL and talked with the owner, Steve, and was happy to hear that I could show everyone a safe way to do this without cutting the plate in the wrong spots. I was sent over to see Wink Eller and show him what I was after. He wasted no time getting the plate up on the cutting block (or mill).
I had marked the plate where I wanted to cut it, but then Wink told me that he had already planned to cut a plate down and knew just how far back he could cut. He then told me that the engineers at BDL had been working on offering something along these lines in the future. They just hadn't put the last details together yet, so this was a good time to do it.
Here is the backing plate...
Here is the backing plate on the bike. I marked the backing plate where I needed to remove the extra aluminum to lighten it up.
We placed the backing plate...
We placed the backing plate on a scale just to see how much it weighed. At 15 lbs, it could stand to lose some weight.
After Wink took all the info...
After Wink took all the info off the plate, he handed it over to Carlos to place in the CNC machine and then bolted it in position.
At first, I figured that this...
At first, I figured that this would need to be done by hand on a mill, but after the CNC was programmed, all we needed to do was sit back and watch it work.
You know this would be messy...
You know this would be messy as hell if we tried to take the photos with the coolant running over the bit, so we needed to stop the CNC to take the photos. After the first pass along the bottom, you can see where the material was cut off. We were told that each cut needed to be done three times about 1 inch at a time to make it clean.
After the first three passes,...
After the first three passes, the lower side was cut down. After all the outer perimeters were cut down, then the last pass would cut slower and cleaner.
Here is the backing plate....
Here is the backing plate. At this point it's still raw-cut and needs to get the final cut to smooth out all the burrs.
Then the bit was changed on...
Then the bit was changed on the CNC, and the outer edge was bevel-cut slow and smooth.
In less than 30 minutes, we...
In less than 30 minutes, we had the plate cut down. It took a lot more time to program the CNC machine than to actually cut the plate.
Carlos cleaned off all the...
Carlos cleaned off all the coolant and pulled it out of the CNC. You can see a big difference in the plate. I couldn't wait to get it back on the bike.
Before we reinstalled the...
Before we reinstalled the plate on the bike, we placed it back on the scale. It weighed in right around 9 lbs, which means they shaved off almost 6 lbs!
I placed the backing plate...
I placed the backing plate back on the bike. Now I have a custom-looking beltdrive.
I wanted to point out that...
I wanted to point out that this also made more clearance for the shift linkage.
There you have it-with 6 lbs...
There you have it-with 6 lbs gone from the backing plate, you could say we trimmed the fat and thinned it down to race weight. When we were done, the whole shop liked it so much that it is now in full production and available through CCI.