In 2013 we bought a TD-23-3 disk for our KT100 with a 10t drum. We ran it at our nearby sprint track (Sandy Hook Speedway) twice and it worked well. However we noticed the bronze bushing in the drum was worn and needed to be changed, a common issue with the Tomar drums. We tapped the bushing out and put a new one in, but when we mounted it on the crank the drum cracked. This was the night before the last race of the season so we were deeply upset. Now, I’ve read that this was a problem before, and now I’m looking to buy another drum, but for over 50$ it’s not something I want to see break again. Has anyone had a similar experience with the 10t drums? Does the cracking issue still persist?
I had a customer break allot of those 10th gears on the TD23-3 and lost him the championship. They made the gear thinner so you can press in a full size bushing and not have to ream it. The 11th is ok but you can’t get the gear ratio you need for Sandy Hook. Sell it or keep it for a longer track.
FAA certified jet engine and aircraft technician,
Nicholson Speedway class champion 2001,
Yamaha KT100 Service Center,
41 years karting experience
I knew you’d have the answer Walt. Glad to have an explanation for the failure. We are going to try and run it as a direct drive now. Not looking to run for points or anything, since no one runs it anymore. Just looking to get more practice on the sprint tracks.
Just a thought Andrews Racing is getting out of the clutch drum business and they are selling drums cheap! $32. on eBay they had both Horstman and Tomar drums. I bought a 10 and 11 tooth drum they look nice, haven’t used them yet.