Need more torque, keep burning up clutches.
- Thread starter Aerindel
- Start date
Probably much lower RPMs and maybe some lugging. The Comet seems to need much lower sprocket ratios. I was running 3100 rpm garter springs, a 7” driver and 9/70 sprockets to get the hill climbing performance I wanted out of the Comet. Even with a good cleaning and moly dry lube, it would start to stick after 20-30 minutes of riding. I was getting ready to try aluminum weights, speed limiting weights, or shift restricting bushings when the Juggernaut came out.
I’ve still got a genuine Comet driver around. Maybe I can get him to make a second video with it. Also need to make a video of the bike since I backed out the throttle screw. Makes a governed 5000 rpms with no adjustment. It wants to pick the front wheel up on the hill.
I’ve still got a genuine Comet driver around. Maybe I can get him to make a second video with it. Also need to make a video of the bike since I backed out the throttle screw. Makes a governed 5000 rpms with no adjustment. It wants to pick the front wheel up on the hill.
Links for a Chinese TAV and a Juggernaut for $150ish. You might throw in a 8 tooth sprocket and save on chain/rear sprocket.
https://www.ebay.com/itm/284922279247?hash=item4256b0f54f:g:WsMAAOSw9JRlOK80&amdata=enc:AQAIAAAAsG8lV8VPGVmouIcY2HPRY+Ge+/EI1aY5xqCmdTLXDJKCB89lI1Ru1yaqlQXFSRKQNMInYL+VBgBcPwZkFGmpHyZwmZt5XwbZ2rfxTPpsJjET/AI/M7XrCA+/NyNFExc0JqPL1SrMD7NG2iISAQRs3c0dujz3L4GqaAKDp/aSmGPJDENJf/4/8By0Kbe3GuKDlW1J8vXQPkkR6z8oCa5gDPSCoPfUxuvPoIX0GQ6meaLM|tkp:Bk9SR_q69rqmYw
https://www.ebay.com/itm/334982493843?hash=item4dfe833693:g:uLUAAOSwzbpk08bw&amdata=enc:AQAIAAAA4Kwkv8FgigITqeXNd+wEi1DWWtp4Vu7yxJTmLQJHutLfDv1vd5p0m1DLK8gBBYU8Kfi5IlWP76xaql7TrPEgqECShTDO0emZefouFs9toawm+f+DV2oUdVrgpDceXXEAZUR2emn/pOV0aFk9KFVoqjz3bCflW1lM6YKqDg6ApMQMGG8cH8kgunkX6ydDOyaLkXC2LdIPGbH4uStNC43K5gKkcK+70pb6VD42TelLrFGP4Tn1agE6E0wJ48DdCqswX/zRP00l1aiMJ94LjFSJ/0khtGhvI6lcaL2SAwCwGMor|tkp:Bk9SR66_grumYw
https://www.ebay.com/itm/284922279247?hash=item4256b0f54f:g:WsMAAOSw9JRlOK80&amdata=enc:AQAIAAAAsG8lV8VPGVmouIcY2HPRY+Ge+/EI1aY5xqCmdTLXDJKCB89lI1Ru1yaqlQXFSRKQNMInYL+VBgBcPwZkFGmpHyZwmZt5XwbZ2rfxTPpsJjET/AI/M7XrCA+/NyNFExc0JqPL1SrMD7NG2iISAQRs3c0dujz3L4GqaAKDp/aSmGPJDENJf/4/8By0Kbe3GuKDlW1J8vXQPkkR6z8oCa5gDPSCoPfUxuvPoIX0GQ6meaLM|tkp:Bk9SR_q69rqmYw
https://www.ebay.com/itm/334982493843?hash=item4dfe833693:g:uLUAAOSwzbpk08bw&amdata=enc:AQAIAAAA4Kwkv8FgigITqeXNd+wEi1DWWtp4Vu7yxJTmLQJHutLfDv1vd5p0m1DLK8gBBYU8Kfi5IlWP76xaql7TrPEgqECShTDO0emZefouFs9toawm+f+DV2oUdVrgpDceXXEAZUR2emn/pOV0aFk9KFVoqjz3bCflW1lM6YKqDg6ApMQMGG8cH8kgunkX6ydDOyaLkXC2LdIPGbH4uStNC43K5gKkcK+70pb6VD42TelLrFGP4Tn1agE6E0wJ48DdCqswX/zRP00l1aiMJ94LjFSJ/0khtGhvI6lcaL2SAwCwGMor|tkp:Bk9SR66_grumYw
Look, here is a mini bike speed calculator, It's gonna be close.
http://www.csgnetwork.com/minibikepotentialspeedcalc.html
The tc is a good start. I wouldn't change the rear sprocket until that is installed and you have run the bike around for at least a little bit. I believe most people go ahead and add a 60 tooth rear sprocket at the same time.
My bike and I weigh about 360 lbs. 180 and 180. Well since before Christmas and New Year.
. I have a 47" wheelbase. That puts my butt torwards the front of the rear tire. I'm running a stock 212 predator with only the throttle screw backed out. Using a chinese tc with the driven spring in the middle hole, 8 tooth driven sprocket and 72t rear sprocket, for a 9:1 ratio, 19x7-8 tires. Top rpm is around 4000.
I started out with 10 tooth/60 tooth sprockets and worked my way down. One sprocket change at a time.
With that gearing, tires, and rpm, my top speed is around 27,28 mph. That is after the tc belt has shifted into the aprox. 10% overdrive which turns that 9:1 into about 8.1:1 final drive ratio.
Even with the rear axle behind me, I can still pull the front tire off the ground a little bit on a full throttle launch at about 2500 rpm, and if I slide just a little backwards on the seat it will stand up. But I'm hitting a little flat spot between the launch till about 3000 rpm. Between 3k and 4k throttle is fairly responsive. Same with cruising, if I'm below 3k throttle feels a little sluggish, about 3 to 4 pretty good. I'm slowly working on that. Even the tc may need tuning.
Point is, nothing is engaved in stone. You are going to have to find out what works for you. Either more power, less weight, or lower gearing.
http://www.csgnetwork.com/minibikepotentialspeedcalc.html
The tc is a good start. I wouldn't change the rear sprocket until that is installed and you have run the bike around for at least a little bit. I believe most people go ahead and add a 60 tooth rear sprocket at the same time.
My bike and I weigh about 360 lbs. 180 and 180. Well since before Christmas and New Year.
. I have a 47" wheelbase. That puts my butt torwards the front of the rear tire. I'm running a stock 212 predator with only the throttle screw backed out. Using a chinese tc with the driven spring in the middle hole, 8 tooth driven sprocket and 72t rear sprocket, for a 9:1 ratio, 19x7-8 tires. Top rpm is around 4000.I started out with 10 tooth/60 tooth sprockets and worked my way down. One sprocket change at a time.
With that gearing, tires, and rpm, my top speed is around 27,28 mph. That is after the tc belt has shifted into the aprox. 10% overdrive which turns that 9:1 into about 8.1:1 final drive ratio.
Even with the rear axle behind me, I can still pull the front tire off the ground a little bit on a full throttle launch at about 2500 rpm, and if I slide just a little backwards on the seat it will stand up. But I'm hitting a little flat spot between the launch till about 3000 rpm. Between 3k and 4k throttle is fairly responsive. Same with cruising, if I'm below 3k throttle feels a little sluggish, about 3 to 4 pretty good. I'm slowly working on that. Even the tc may need tuning.
Point is, nothing is engaved in stone. You are going to have to find out what works for you. Either more power, less weight, or lower gearing.
Look, here is a mini bike speed calculator, It's gonna be close.
http://www.csgnetwork.com/minibikepotentialspeedcalc.html
The tc is a good start. I wouldn't change the rear sprocket until that is installed and you have run the bike around for at least a little bit. I believe most people go ahead and add a 60 tooth rear sprocket at the same time.
My bike and I weigh about 360 lbs. 180 and 180. Well since before Christmas and New Year.. I have a 47" wheelbase. That puts my butt torwards the front of the rear tire. I'm running a stock 212 predator with only the throttle screw backed out. Using a chinese tc with the driven spring in the middle hole, 8 tooth driven sprocket and 72t rear sprocket, for a 9:1 ratio, 19x7-8 tires. Top rpm is around 4000.
I started out with 10 tooth/60 tooth sprockets and worked my way down. One sprocket change at a time.
With that gearing, tires, and rpm, my top speed is around 27,28 mph. That is after the tc belt has shifted into the aprox. 10% overdrive which turns that 9:1 into about 8.1:1 final drive ratio.
Even with the rear axle behind me, I can still pull the front tire off the ground a little bit on a full throttle launch at about 2500 rpm, and if I slide just a little backwards on the seat it will stand up. But I'm hitting a little flat spot between the launch till about 3000 rpm. Between 3k and 4k throttle is fairly responsive. Same with cruising, if I'm below 3k throttle feels a little sluggish, about 3 to 4 pretty good. I'm slowly working on that. Even the tc may need tuning.
Point is, nothing is engaved in stone. You are going to have to find out what works for you. Either more power, less weight, or lower gearing.
http://www.csgnetwork.com/minibikepotentialspeedcalc.html
The tc is a good start. I wouldn't change the rear sprocket until that is installed and you have run the bike around for at least a little bit. I believe most people go ahead and add a 60 tooth rear sprocket at the same time.
My bike and I weigh about 360 lbs. 180 and 180. Well since before Christmas and New Year.
. I have a 47" wheelbase. That puts my butt torwards the front of the rear tire. I'm running a stock 212 predator with only the throttle screw backed out. Using a chinese tc with the driven spring in the middle hole, 8 tooth driven sprocket and 72t rear sprocket, for a 9:1 ratio, 19x7-8 tires. Top rpm is around 4000.I started out with 10 tooth/60 tooth sprockets and worked my way down. One sprocket change at a time.
With that gearing, tires, and rpm, my top speed is around 27,28 mph. That is after the tc belt has shifted into the aprox. 10% overdrive which turns that 9:1 into about 8.1:1 final drive ratio.
Even with the rear axle behind me, I can still pull the front tire off the ground a little bit on a full throttle launch at about 2500 rpm, and if I slide just a little backwards on the seat it will stand up. But I'm hitting a little flat spot between the launch till about 3000 rpm. Between 3k and 4k throttle is fairly responsive. Same with cruising, if I'm below 3k throttle feels a little sluggish, about 3 to 4 pretty good. I'm slowly working on that. Even the tc may need tuning.
Point is, nothing is engaved in stone. You are going to have to find out what works for you. Either more power, less weight, or lower gearing.
Look, here is a mini bike speed calculator, It's gonna be close.
http://www.csgnetwork.com/minibikepotentialspeedcalc.html
The tc is a good start. I wouldn't change the rear sprocket until that is installed and you have run the bike around for at least a little bit. I believe most people go ahead and add a 60 tooth rear sprocket at the same time.
My bike and I weigh about 360 lbs. 180 and 180. Well since before Christmas and New Year.. I have a 47" wheelbase. That puts my butt torwards the front of the rear tire. I'm running a stock 212 predator with only the throttle screw backed out. Using a chinese tc with the driven spring in the middle hole, 8 tooth driven sprocket and 72t rear sprocket, for a 9:1 ratio, 19x7-8 tires. Top rpm is around 4000.
I started out with 10 tooth/60 tooth sprockets and worked my way down. One sprocket change at a time.
With that gearing, tires, and rpm, my top speed is around 27,28 mph. That is after the tc belt has shifted into the aprox. 10% overdrive which turns that 9:1 into about 8.1:1 final drive ratio.
Even with the rear axle behind me, I can still pull the front tire off the ground a little bit on a full throttle launch at about 2500 rpm, and if I slide just a little backwards on the seat it will stand up. But I'm hitting a little flat spot between the launch till about 3000 rpm. Between 3k and 4k throttle is fairly responsive. Same with cruising, if I'm below 3k throttle feels a little sluggish, about 3 to 4 pretty good. I'm slowly working on that. Even the tc may need tuning.
Point is, nothing is engaved in stone. You are going to have to find out what works for you. Either more power, less weight, or lower gearing.
http://www.csgnetwork.com/minibikepotentialspeedcalc.html
The tc is a good start. I wouldn't change the rear sprocket until that is installed and you have run the bike around for at least a little bit. I believe most people go ahead and add a 60 tooth rear sprocket at the same time.
My bike and I weigh about 360 lbs. 180 and 180. Well since before Christmas and New Year.
. I have a 47" wheelbase. That puts my butt torwards the front of the rear tire. I'm running a stock 212 predator with only the throttle screw backed out. Using a chinese tc with the driven spring in the middle hole, 8 tooth driven sprocket and 72t rear sprocket, for a 9:1 ratio, 19x7-8 tires. Top rpm is around 4000.I started out with 10 tooth/60 tooth sprockets and worked my way down. One sprocket change at a time.
With that gearing, tires, and rpm, my top speed is around 27,28 mph. That is after the tc belt has shifted into the aprox. 10% overdrive which turns that 9:1 into about 8.1:1 final drive ratio.
Even with the rear axle behind me, I can still pull the front tire off the ground a little bit on a full throttle launch at about 2500 rpm, and if I slide just a little backwards on the seat it will stand up. But I'm hitting a little flat spot between the launch till about 3000 rpm. Between 3k and 4k throttle is fairly responsive. Same with cruising, if I'm below 3k throttle feels a little sluggish, about 3 to 4 pretty good. I'm slowly working on that. Even the tc may need tuning.
Point is, nothing is engaved in stone. You are going to have to find out what works for you. Either more power, less weight, or lower gearing.
Now I just need to go shopping. I have the 5/8th crankshaft on mine so need to find the right TC or sleeve.
Please don't make to hasty of a decision on what you want to do. I don't know and I don't sleep at the Holiday Inn Express, but you might be in a situation where you are going to need to power up your motor or put a 224 or even a big block on and stretch your wheel base like @MJL did. Especially if your dealing with steep inclines.
Keep the 5 P's in mind proper planning prevents p*ss poor performance.
Keep the 5 P's in mind proper planning prevents p*ss poor performance.
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I’d just swap the crankshaft. Probably wise to check the rod clearance with plastiguage, or you could just compare it to the existing crankshaft with calipers.
https://www.ebay.com/itm/1642302375...F51a1lTXAP5DsWq2VYkpDpmT6b|tkp:Bk9SR7rR7oCnYw
https://www.ebay.com/itm/1642302375...F51a1lTXAP5DsWq2VYkpDpmT6b|tkp:Bk9SR7rR7oCnYw
Please don't make to hasty of a decision on what you want to do. I don't know and I don't sleep at the Holiday Inn Express, but you might be in a situation where you are going to need to power up your motor or put a 224 or even a big block on and stretch your wheel base like @MJL did. Especially if your dealing with steep inclines.
Keep the 5 P's in mind proper planning prevents p*ss poor performance.
Keep the 5 P's in mind proper planning prevents p*ss poor performance.
This is not my primary 'toy'......more of just an easy way to get around my 10 acres of hillside. When I'm in a mood to put real work into something, I save that for my DoomBuggy.
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Well, crap.
I got a 5/8th to 3/4 sleeve adapter, but now that my torque converter kit arrived, I see that the key on the driver pulley is built into the part, so there is no way to key the driver to the crankshaft.
And oddly, I have no trouble finding 3/4 drivers with 5/8 jackshaft driven, the reverse is not true.
I got a 5/8th to 3/4 sleeve adapter, but now that my torque converter kit arrived, I see that the key on the driver pulley is built into the part, so there is no way to key the driver to the crankshaft.
And oddly, I have no trouble finding 3/4 drivers with 5/8 jackshaft driven, the reverse is not true.
The 30 series only come with a 3/4" or a 1" driver.
I don't know how guys use those adaptors. You are putting a sleeve on the crankshaft that is designed for 5/8" on a 16mm shaft. You would think it would open up making putting on the fixed sheeve difficult. And you mentioned the built in keys. I've never tried using one.
I like working on these things and would get a $30 crankshaft. Using an adaptor wouldn't be as fun.
I don't know how guys use those adaptors. You are putting a sleeve on the crankshaft that is designed for 5/8" on a 16mm shaft. You would think it would open up making putting on the fixed sheeve difficult. And you mentioned the built in keys. I've never tried using one.
I like working on these things and would get a $30 crankshaft. Using an adaptor wouldn't be as fun.
Its fairly trivial to 'lathe' the driveshaft the 4/1000ths of an inch smaller it needs to be with the engine running and a file, its such a small difference.
I....dislike taking apart things with seals.....If I have to have a 3/4 driveshaft, I will just buy a predator engine and get a little more power at the same time. Maybe its silly, but seals give me PTSD....I'll pull a car engine without worrying, but make me replace a seal and I start sweating.
I like having things....I hate working on things....however nobody ever seems to make what I actually want at a price I can afford so I have spent my life making things....including my whole house....
But I never like it.
I think I can make it work. Part of the keyway is covered by a spacer, so for that part, I can easily use the key, which will mechanically lock the space to the shaft For the rest of it, I think I can just JB weld the spacer to the shaft, as the key in the driver will engage the spacer, but not the shaft, but should be fine as long as the spacer is secure.
And if it all blows up on me, I have a fallback plan of just getting a Predator 212 with 3/4 shaft for about $150.
I'm trying to convince myself I'm having fun.
I....dislike taking apart things with seals.....If I have to have a 3/4 driveshaft, I will just buy a predator engine and get a little more power at the same time. Maybe its silly, but seals give me PTSD....I'll pull a car engine without worrying, but make me replace a seal and I start sweating.
I like having things....I hate working on things....however nobody ever seems to make what I actually want at a price I can afford so I have spent my life making things....including my whole house....
But I never like it.
I think I can make it work. Part of the keyway is covered by a spacer, so for that part, I can easily use the key, which will mechanically lock the space to the shaft For the rest of it, I think I can just JB weld the spacer to the shaft, as the key in the driver will engage the spacer, but not the shaft, but should be fine as long as the spacer is secure.
And if it all blows up on me, I have a fallback plan of just getting a Predator 212 with 3/4 shaft for about $150.
I'm trying to convince myself I'm having fun.
Well, I think It will work.
I lathed down the 16mm shaft to make it 5/8, this wasn't a problem, took maybe five minutes, just ran the engine and held a old belt grinder belt against the shaft.
I then ground down my key, until it was flush with the sleeve, and trimmed it down to about 1" long, which is as long as it can be without interfering with the built in key of the driver unit.
BTW, I still have no idea how the driver works. I mean, I know that it must pull the cone innward at higher RPM....I just don't understand HOW it does that, but I guess I will trust that it does.
Only thing I need now, is a 6mm bolt long enough, which I don't have so I have to go make a two hour trip to town and go bolt hunting.
I lathed down the 16mm shaft to make it 5/8, this wasn't a problem, took maybe five minutes, just ran the engine and held a old belt grinder belt against the shaft.
I then ground down my key, until it was flush with the sleeve, and trimmed it down to about 1" long, which is as long as it can be without interfering with the built in key of the driver unit.
BTW, I still have no idea how the driver works. I mean, I know that it must pull the cone innward at higher RPM....I just don't understand HOW it does that, but I guess I will trust that it does.
Only thing I need now, is a 6mm bolt long enough, which I don't have so I have to go make a two hour trip to town and go bolt hunting.