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Old 05-27-2020, 04:38 AM
Robert K
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Join Date: Jul 2007
Location: The Netherlands
Posts: 27

Originally Posted by ericric38 View Post
Hi all, first time posting! My name is Eric from Hong Kong and too have the Schumacher Mi7. I put together the kit in March and after a month of social distancing and local tracks reopening, I was able to "test" the Mi7 for the very first time this past Saturday.

First impressions of the car, the build was really nice, the quality and precision of the parts, how everything assembled was just super enjoyable. Before the Mi7, I ran the Destiny RX-10SR 2.0, Xpress XQ1 and SMJ CX-11. none of the build quality compared to the Mi7. I run 13.5 on the Mi7 and the cars I've previously mentioned and the stock settings alone really impressed me. The car was very predictable, responsive and turns in very well. The local track I run the car at has loose grip and bumpy and I have to say the car really handled the track well.

As good as the car is, I have a question I would like to ask all the more experienced racers here on the Mi7 forum and is about spur gears stripping. The kit comes with an arrowmax 32 pitch spur, and I've opted for the 64 pitch AXON spur gears because this is what I've always ran. But for some reason, whenever I break really hard, for example before entering a corner after the main straight, I would hear a gnarly "cracking sound". The track is pretty big and I can hear it from the driver stand outdoors! Few laps later, you guessed it, the spur was stripped. At first i thought it was a bad mesh, so I've had more experienced racers double check multiple times. i know there was nothing wrong with the car, everything was tight and the car was not in any crashes. So I ended the track day with a big question mark on my head...so I decided to see if anyone had that issue before here on the forums.

I use a 13.5T Muchmore Specter motor (old, a direct transplant from my previous car) paired with a "Lee Speed" (local brand) titanium pinion (38 tooth 64 pitch). After the track day, I inspected the center pulley to check for play. There was a little play (0.1mm) from the bearings and the spur gear was screwed on tightly. I then inspected the center pulley by taking it out and turning the spur while it was secured to the center pulley and it didn't bulge (maybe I couldn't really too much force into it before it started to hurt my hand.

Hope I this was enough information about my car. Im really loving it so far minus the annoying spur gear stripping after every pack of battery. But on the flip side, changing the spur gear on this car is a breeze!
Originally Posted by Larrysraceprep View Post
I too have not been able to make the Schumacher brand gears last more than about four minutes you must use a different brand gear Iím actually using 48 pitch in modified for the first time ever but the few times I ran stock it even stripped the 64 pitch Schumacher gears so I went to Axon and Kimbrough havenít had The problem again But a lot of times the cracking sound on the break is the front belt skipping thatís why I added the top deck pitch control brace so the bulkhead doesnít Flex rearward under hard braking
I've been thinking of these post's for a couple of days now. Running indoor 17.5T with a Arrowmax spur gear and even with an Arrowmax 17.5T molded (plastic) pinion I've not had any problems.

Going outdoors with 4.5T Mod I indeed smashed a couple of spur gears mostly under breaking at the end of the straight. Put I couldn't wrap my head around it, but talking with some other MI7 drivers I just didn't mesh my gears right. In stock I had more space between the teeth and tried that with 4.5T mod too. Meshing the gears right I've now had 3 complete day's on one spur gear 4.5T mod without any problems.

What Iím trying to say is that I now have the gears meshed a bit closer, (still have a tiny bit of play) and I'm not having any problems with my gears anymore. Mainly because I forgot how to mesh the gears running mod Hope it Helps

Regards Robert

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