Bbqjoe
Banned
Preface:
I'm putting this in mini bikes, since that's what I ride, but most of this applies to karts too.
Many of you know this stuff, but I thought I'd document some of it for the folks who want or need to learn.
Most of the upcoming parts have the better part of 2000 miles on them, some more, some less.
My morning circuit with the dogs is always 4 miles, but still staying in my "Hood" I can easily extend it to 7 miles, adding a few other legs on the trip.
Other days I might easily venture 15 mi out and back plus my normal circuit, making the day's trip well over 30. It's not hard at all to rack up 2000+ mi in the summer months. I'm expecting even more this summer. All of my riding is done in the desert, in very dry, hot and dusty conditions. It is impossible to keep sand out of anything.
This will be a breakdown of what I'm doing to my machine to get it back in shape for the next few thousand.
We'll start with the chain.
The chain on this sprocket looks, well, It looks like a chain on a sprocket.
This next picture shows you how to check your chain while it's still on your machine.
No matter how tight or loose your chain may be, if you can lift it this high off the middle of the sprocket, what you have is a lunched chain. There is nothing you can do for it, and it needs to be replaced.
Another simple test you can do for chain wear is this. The top chain is new, right out of the package. The bottom one is the same one we just saw on the sprocket.
This test also verifies that this chain is toast. It should not be able to have this much lateral movement.
This particular chain I experimented with using no oil, but just spray on dry moly. I think the moly may have retarded the collection of dust on the outside, but I don't think it did anything for the inside of the rollers. I wasn't able to get a good pic, but the rollers had quite a bit of slop on the pins.
I am going to try a new experiment on the next chain. I gave it a bath in what I sometimes use as a bullet lube. It boiled for an hour or so in a mixture of various oils, waxes, and alox in an old crockpot.
With as much wear as there was on the chain, the rear sprocket deserved some inspection.
The sprocket has only about half as much use as the chain, and I shouldn't have put it on without a new chain, but I didn't.
Here is the sprocket showing a fair amount of wear, mostly due to a wearing chain.
You can see that some teeth are thinner than others.
Looking closer, you can see the smashed metal on the teeth, as well as the curve in the teeth that a worn sprocket will develop. Sometimes it's not so easy to see, but if you put your finger in the cradle between the teeth, you can feel a curve in early wear.
Since I am changing the chain, I'm going to put on a new sprocket as well.
Since I am doing the rear sprocket, the front one on the TC also needs looking at, and in this case, it is completely trashed and needs replacing as well.
While inspecting the TC, I found that the front bearing in the jackshaft had gone south., which might explain how the sprocket got so badly worn.
If you're going to replace the front bearing, might as well replace the back one as well.
I also noticed that the spindle had somehow taken a beating, and that the keyway was badly damaged.
The driver on the TC seems fine, and the driven looks ok too.
I decided to order new bearings, TC sprocket, and shaft. I came to find with ordering the parts separately plus shipping, for a few bucks more I could just get a new TAV 30 knock off for around $70, which is what I ended up doing.
The TC I had came from GTC. Upon arrival of the TAV 30, I was blown away by its size. I tried putting it in place, and found due to it's size, I would have to raise the engine a good inch, or do some serious slicing and dicing on the backplate to get it to fit.
This next picture will show why the GTC plate fits on a machine so much easier.
I came to find that the bearings on the TAV were the exact same make and size as the ones on the GTC. I also noticed that the shaft, driver and driven were also the same, and the same make.
Which is to say, I think all these different makers get their parts from the same place.
The only difference between the GTC and the TAV was the back plate, and about $100. The metal on the plates is about the same thickness.
But being as I didn't want to mess with cutting up the TAV, I just rebuilt the GTC with the tav parts. Leaving me a replacement plate, driver and driven.
Since I had the rear wheel off, and was replacing the sprocket, I went ahead and installed a new tire.
I also pulled the bearings out of the hub for inspection.
These bearings appear to be sealed, but they really aren't. The covers can easily be removed using a small screw driver.
This next picture is what a new bearing looks like with the seal removed.
There is a fair amount of grease in it, but it could stand some more.
The next pic is what a used, un-repacked bearing looks like.
The next one shows the same bearing after being soaked in gasoline, sprayed out with compressed air, and repacked.
The seal is easily pressed back into place with your fingers, then cleaned up.
I will be doing the same procedure to the front wheel bearings as well.
The spark plug looks even better than I expected, and I will continue to use it, especially since the engine runs great, and the oil is changed often.
The belt for the TC was replaced only a couple of weeks ago.
It is the one on the bottom, and cost about $35.
The one in the middle is the one that came with the TAV.
The one on top I ordered off cheesebay for $8.
You can clearly see the quality difference in each belt, and how much actual belt will come into contact with the surfaces on the TC.
So this is where I stand right now. There are still a few more things to inspect and do, I'll try to post them as well.
Good day!
I'm putting this in mini bikes, since that's what I ride, but most of this applies to karts too.
Many of you know this stuff, but I thought I'd document some of it for the folks who want or need to learn.
Most of the upcoming parts have the better part of 2000 miles on them, some more, some less.
My morning circuit with the dogs is always 4 miles, but still staying in my "Hood" I can easily extend it to 7 miles, adding a few other legs on the trip.
Other days I might easily venture 15 mi out and back plus my normal circuit, making the day's trip well over 30. It's not hard at all to rack up 2000+ mi in the summer months. I'm expecting even more this summer. All of my riding is done in the desert, in very dry, hot and dusty conditions. It is impossible to keep sand out of anything.
This will be a breakdown of what I'm doing to my machine to get it back in shape for the next few thousand.
We'll start with the chain.
The chain on this sprocket looks, well, It looks like a chain on a sprocket.
This next picture shows you how to check your chain while it's still on your machine.
No matter how tight or loose your chain may be, if you can lift it this high off the middle of the sprocket, what you have is a lunched chain. There is nothing you can do for it, and it needs to be replaced.
Another simple test you can do for chain wear is this. The top chain is new, right out of the package. The bottom one is the same one we just saw on the sprocket.
This test also verifies that this chain is toast. It should not be able to have this much lateral movement.
This particular chain I experimented with using no oil, but just spray on dry moly. I think the moly may have retarded the collection of dust on the outside, but I don't think it did anything for the inside of the rollers. I wasn't able to get a good pic, but the rollers had quite a bit of slop on the pins.
I am going to try a new experiment on the next chain. I gave it a bath in what I sometimes use as a bullet lube. It boiled for an hour or so in a mixture of various oils, waxes, and alox in an old crockpot.
With as much wear as there was on the chain, the rear sprocket deserved some inspection.
The sprocket has only about half as much use as the chain, and I shouldn't have put it on without a new chain, but I didn't.
Here is the sprocket showing a fair amount of wear, mostly due to a wearing chain.
You can see that some teeth are thinner than others.
Looking closer, you can see the smashed metal on the teeth, as well as the curve in the teeth that a worn sprocket will develop. Sometimes it's not so easy to see, but if you put your finger in the cradle between the teeth, you can feel a curve in early wear.
Since I am changing the chain, I'm going to put on a new sprocket as well.
Since I am doing the rear sprocket, the front one on the TC also needs looking at, and in this case, it is completely trashed and needs replacing as well.
While inspecting the TC, I found that the front bearing in the jackshaft had gone south., which might explain how the sprocket got so badly worn.
If you're going to replace the front bearing, might as well replace the back one as well.
I also noticed that the spindle had somehow taken a beating, and that the keyway was badly damaged.
The driver on the TC seems fine, and the driven looks ok too.
I decided to order new bearings, TC sprocket, and shaft. I came to find with ordering the parts separately plus shipping, for a few bucks more I could just get a new TAV 30 knock off for around $70, which is what I ended up doing.
The TC I had came from GTC. Upon arrival of the TAV 30, I was blown away by its size. I tried putting it in place, and found due to it's size, I would have to raise the engine a good inch, or do some serious slicing and dicing on the backplate to get it to fit.
This next picture will show why the GTC plate fits on a machine so much easier.
I came to find that the bearings on the TAV were the exact same make and size as the ones on the GTC. I also noticed that the shaft, driver and driven were also the same, and the same make.
Which is to say, I think all these different makers get their parts from the same place.
The only difference between the GTC and the TAV was the back plate, and about $100. The metal on the plates is about the same thickness.
But being as I didn't want to mess with cutting up the TAV, I just rebuilt the GTC with the tav parts. Leaving me a replacement plate, driver and driven.
Since I had the rear wheel off, and was replacing the sprocket, I went ahead and installed a new tire.
I also pulled the bearings out of the hub for inspection.
These bearings appear to be sealed, but they really aren't. The covers can easily be removed using a small screw driver.
This next picture is what a new bearing looks like with the seal removed.
There is a fair amount of grease in it, but it could stand some more.
The next pic is what a used, un-repacked bearing looks like.
The next one shows the same bearing after being soaked in gasoline, sprayed out with compressed air, and repacked.
The seal is easily pressed back into place with your fingers, then cleaned up.
I will be doing the same procedure to the front wheel bearings as well.
The spark plug looks even better than I expected, and I will continue to use it, especially since the engine runs great, and the oil is changed often.
The belt for the TC was replaced only a couple of weeks ago.
It is the one on the bottom, and cost about $35.
The one in the middle is the one that came with the TAV.
The one on top I ordered off cheesebay for $8.
You can clearly see the quality difference in each belt, and how much actual belt will come into contact with the surfaces on the TC.
So this is where I stand right now. There are still a few more things to inspect and do, I'll try to post them as well.
Good day!
