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Post by Keith Tanaka on Jun 25, 2014 16:09:52 GMT -8
Prior to the start of the 4 hour enduro I thought that we would need to make a motor change and replace the rear tires at least once during the race. After the race ended, it was a big surprise (to me) that everyone ran the entire enduro with one motor and most if not all used only one set of tires. Today, I checked the two cars I built/raced for the race (one was raced by team #4 "Survivors") and I was very surprised by what I found. Team "Senior Discount" car: motor: TSR D3, one motor brush nearly 100% worn, other brush 75% worn. Geared 11/54 rear tires: almost no measurable wear (hard to believe?). Rear clearance still passes tech (.050" min.). Team #4 "Survivors" car: motor: Falcon 7, one motor brush nearly 100% worn, other brush 70% worn. Geared 10/49 rear tires: almost no measurable wear (again hard to believe?). Rear clearance still passes tech. Did anyone else notice the motor and tire wear of their enduro car? Tire wear question. Why was the tire wear negligible? Do the conditions of an enduro extend the life of the tires versus a regular monthly race condition? If so, how? Comments? Keith
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Post by bob krigbaum on Jun 25, 2014 22:35:20 GMT -8
Keith, Sloth Racing had to change tires during the 11th heat but the second pair lasted until the end. The car finished with only .030 rear clearance. We were geared 10/52 and our motor still has at least 25% brush left on both sides of the TSR. We may have been the only team that had to change tires. Perhaps my chassis was harder on tires, our car was loose the entire race. I set it up that way expecting the car to tighten up as the race went along but it never did. I'm still amazed with the motors, we had two extras ready to go and I fully expected to have to use them both. I spoke to Tim Neja afterwards and they had the same motor plan I had, I think everyone was surprised with their longevity. We did have gear wear, our aluminum spur is almost completely shot.
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Post by craigg on Jun 26, 2014 16:55:13 GMT -8
Team Rolling Hill's motor still had a substantial amount of brush wear to go. I don't know what thickness they start at but I would guess that they would have lasted two more hours. We were the lightest at 167gm and geared 11/56. We were running a heat sink also. We ended up with about .040 clearance at the end, so tire wear was not bad, mostly on the right side. We were ready for motor, tire and braid changes, but did not need them. I just put the Slick 7 composite gear on another car, it is just broken in.
I miked the brushes, one was .087 and the other was .092. I don't know the starting measurement. Further disassembly shows .005 wear on the commutator.
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Post by darkron9 on Jun 27, 2014 7:58:08 GMT -8
I didn't participate, but I have a question for the teams.
Which tires did your teams use? I've noticed that the $11 Pro-Track SBR tires wear out much quicker than the $12 Pro-Track natural rubber tires.
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Post by craigg on Jun 27, 2014 12:09:07 GMT -8
Ron, I believe everyone was running the treated Pro Track's. The "N" natural tires have too much grip for heavy cars and wear out faster. A look at the tech sheets on the race report would verify this.
I was wrong, three of the cars were running N tires and five treated tires.
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timneja
Full Member
Love racing these hard body cars!! The new knee is working better--so I'll be back soon!!
Posts: 191
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Post by timneja on Jun 29, 2014 8:32:23 GMT -8
Our brush wear was very similar to what Keith experienced in the Bowtie car. But tire wear was going to be a problem if we ran much longer. I'd estimate we were down to .020 clearance at the end!! I think it was the Pro Track treated tires we ran--and our car was just a little "loose"--but it made it easy to drive for those long stints!!
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Post by Keith Tanaka on Jul 17, 2014 16:09:04 GMT -8
Here's photos of the brush wear on two 4 hr. enduro cars. The first motor is a TSR D3 for Team Senior Discount. Car weight 180 g., geared 11/54 The second motor is a Falcon 7 for Team "Survivors". Car weight 181 g., geared 10/49 Both motors had one brush almost worn down completely while the other brush had about 30 to 40% left. Most likely both motors would have lasted another 30 minutes before they lost their brakes. Keith
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timneja
Full Member
Love racing these hard body cars!! The new knee is working better--so I'll be back soon!!
Posts: 191
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Post by timneja on Jul 17, 2014 16:39:06 GMT -8
WOW----maybe we need to go to a 5 hour enduro---to ensure a motor change and tire change!! That would be interesting to see how quickly people can get motors in and out of these babies and change tires. Probably one pit stop and do both at the same time would be the best!! I'd just plan on changing around the 3.5 hour mark--that way a team could probably get away with one stop if there are no other problems!!
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Post by craigg on Jul 17, 2014 21:20:58 GMT -8
Team Rolling Hills' car had another 2-3 hours left with no tire or motor issues. It also was built with fast motor changes in mind, one tire set screw, two motor screws and put the braid back in. Just a tire change could have been done without pulling the body.
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