I have a Tav30 with the steel stamped backplate installed on my Kenbar MB-6 minibike. It has a Tecumseh 6hp OHV engine. #41 type chain, wheel sprocket is probably 72 tooth though I haven't counted it yet. Looks like the same one on the Manco Thunderbird. Almost the same size as my 480/400x8" rear tire.. Which probably isn't that good back on trails covered with branches, fallen trees, sticks, all sorts of crap. Easy for something to cause damage to it.
Anyway, I was back on the state land today, rode probably around 12 miles just fine, went up about 1/4 mile up a path I haven't gone on before, and threw the chain. It jammed TIGHT in between the sprocket and the frame. You couldn't even turn the wheel, and this bike weighs 175lbs, and I was 1 mile into the wilderness from the nearest paved road... NO TOOLS with me.. (Yeah, dumber all the time, right?) NO WAY was I going to leave my bike, and walk out! Maybe I couldn't pick it up and get it out, but I bet you a dollar, it wouldn't be there when I got back...
Anyway, thank God for deer hunters! I had gone by an old deer blind that was abandoned. In fact, the chain threw almost in front of it. First blind I've ever seen back there. I went to it, and looked inside to see if there was anything to help. Well, lookie here! 2 chunks of 2x4, and 2 chunks of 4x4 wood! Just the sort of things to help... I used the 4x4's under the bike, to prop the rear wheel off the ground. I was able to use the 2x4 pieces, to wedge the chain up a little bit, which allowed me to pull it back up on the sprocket, and feed it back around.
I think I drove over a small tree, which wedged in between the sprocket and chain, and that's what pulled it off. It is not really loose, but the chain might be damaged or stretched a little now. The previous owner said he replaced it this year with one from the local TSC store, so I don't know the original quality of the chain. Anyway, I slowly drove/limped back home, (2 miles, 1 mile to the paved road, and 1 mile to my house) Oh yeah, I put the wood pieces back in the blind before leaving, never know when they might come in handy again.....
Ok, after getting home and looking things over, I noticed that there is a cracked weld on the back of the tav plate, where the driven shaft runs on the bearings. So, I'm going to have to remove the plate, and get that re-welded. Since I have to do that anyway, can anybody tell me exactly what they have done to strengthen the stamped plate? I keep reading here and there about "welding some pieces of "L" metal" on it, but can't find a posting that explains exactly where and how they did this?
I did see a post where the person made a second plate, and mounted it to the engine cover bolts, to help support that bearing shaft that sticks out.
Anyway, I got out safe, and learned some lessons:
1: Carry some tools!
2: Lube your chain more frequently, and check for possible damage from previous riding!
Any advice on fixing this, and improving it, is welcome! I'm also going to replace this chain, as I won't trust it now.
Anyway, I was back on the state land today, rode probably around 12 miles just fine, went up about 1/4 mile up a path I haven't gone on before, and threw the chain. It jammed TIGHT in between the sprocket and the frame. You couldn't even turn the wheel, and this bike weighs 175lbs, and I was 1 mile into the wilderness from the nearest paved road... NO TOOLS with me.. (Yeah, dumber all the time, right?) NO WAY was I going to leave my bike, and walk out! Maybe I couldn't pick it up and get it out, but I bet you a dollar, it wouldn't be there when I got back...
Anyway, thank God for deer hunters! I had gone by an old deer blind that was abandoned. In fact, the chain threw almost in front of it. First blind I've ever seen back there. I went to it, and looked inside to see if there was anything to help. Well, lookie here! 2 chunks of 2x4, and 2 chunks of 4x4 wood! Just the sort of things to help... I used the 4x4's under the bike, to prop the rear wheel off the ground. I was able to use the 2x4 pieces, to wedge the chain up a little bit, which allowed me to pull it back up on the sprocket, and feed it back around.
I think I drove over a small tree, which wedged in between the sprocket and chain, and that's what pulled it off. It is not really loose, but the chain might be damaged or stretched a little now. The previous owner said he replaced it this year with one from the local TSC store, so I don't know the original quality of the chain. Anyway, I slowly drove/limped back home, (2 miles, 1 mile to the paved road, and 1 mile to my house) Oh yeah, I put the wood pieces back in the blind before leaving, never know when they might come in handy again.....
Ok, after getting home and looking things over, I noticed that there is a cracked weld on the back of the tav plate, where the driven shaft runs on the bearings. So, I'm going to have to remove the plate, and get that re-welded. Since I have to do that anyway, can anybody tell me exactly what they have done to strengthen the stamped plate? I keep reading here and there about "welding some pieces of "L" metal" on it, but can't find a posting that explains exactly where and how they did this?
I did see a post where the person made a second plate, and mounted it to the engine cover bolts, to help support that bearing shaft that sticks out.
Anyway, I got out safe, and learned some lessons:
1: Carry some tools!
2: Lube your chain more frequently, and check for possible damage from previous riding!
Any advice on fixing this, and improving it, is welcome! I'm also going to replace this chain, as I won't trust it now.
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