I bought my first minibike in 1971, and it had a Tecumseh motor. So i grew up with these and learned a lot about them "back in the day". Fast forward a zillion years to today, and i've been collecting vintage bikes. And one thing is clear... most don't have their original motors (at least the ones i've been coming across). Heck most don't have *any* motor. And i'm not a Predator guy, i just don't like those, especially installed in a 1970s mini bike.
So with this in mind, i've been collecting Tecumseh 4hp and 5hp engines. Figuring i can't have enough of them, as i'll eventually need them for some random mini bike i come across. So far that theory has proved itself to be pretty true.
Now are you going to find 1969-1972 mini bike designed 4 and 5hp motors out there? Heck no. At least not for a decent price. If you're a "numbers matching" type guy, you should probably stop here and go to ebay... Because we're not getting that anal here. We just want a decent 4/5hp Tecumseh motor with the correct "look", and at a decent price.
So where do you get old Tecumseh flat heads? Well around here (Michigan), snow blowers are the donors. Winters in lower Michigan are pretty tame, but can be snowy, so snow blowers are A) common, and B) lightly used. Perfect donors. But with this in mind, you have to find the right motors (the right snow blowers.) Again I'm looking only for 4hp and 5hp Tecumseh motors. Tecumseh 3.5hp and lower won't work (they won't move my fat ass). Larger than 5hp won't work either (because of the lack of a HS motor size).
Edgers and leaf blowers are not ideal donors. Snowblowers are the best. why? the motors are just cleaner. No or little dirt to deal with (because they get used only during snow!) No air cleaners on snow blowers, because, well, why would you need one during the winter snow? It's pretty perfect for our purposes, with some modifications.
To get a Tecumseh 4 or 5hp, need to look for a snowblower in the 20" to 24" range. Wider than that and you'll be in the 6hp or larger range. Also personally i like old Craftsmen and Ariens models from the 1970s and 1980s. If they have points/condensor that's awesome, though not necessary. Pretty much any flat head until they get the "cyclone" style pull start (want the traditional 4 leg pull start, if possible.) Mind you the "cyclone" starter models are still good motors - they made these well into the 2000s. But the "look" isn't quite vintage (though the motors themselves are fine). We can 'fix' that look with older style decals later. So don't completely disregard these models, if one comes up for sale at a nice price.
Speaking of price, how much do these sell for? Well in the summer, snowblowers tend to be cheap. And older ones (not running) even cheaper. I've bought them from $10 to $75. Remove the motor, put the rest at the curb, and the metal scrapers get it and make it disappear!
Note you need to look at the PTO shaft on the motor. 3/4" is obviously the mini bike standard and what you want. A tapered PTO is the least desirable. 1" is also seen (and is OK.) but 3/4" is ideal. Don't worry if it's drilled or not. If it's a good motor and it's not 3/4" PTO, that's still OK, just a bit more work.
And i should mention that some snow blowers have a second small PTO (used for reverse often). No worries! Don't let a perfectly good motor pass if it has that. We can deal with it...
The one disadvantage to snow blower motors is the flywheels. It's steel and it's heavy. This is unlike "made for minibike" Tecumseh motors, that have an allow flywheel. This isn't a huge deal. I wish snow blower had the alloy flywheel, but they don't. It's OK though. It's not as big a deal as some may think.
I should also mention that i am by NO MEANS an expert on vintage Tecumseh flat heads. All i can tell you is what has worked for me (in the following posts.) There's a lot of compromises that will drive the "purists" crazy. I'm sorry about that. But here we go....
So with this in mind, i've been collecting Tecumseh 4hp and 5hp engines. Figuring i can't have enough of them, as i'll eventually need them for some random mini bike i come across. So far that theory has proved itself to be pretty true.
Now are you going to find 1969-1972 mini bike designed 4 and 5hp motors out there? Heck no. At least not for a decent price. If you're a "numbers matching" type guy, you should probably stop here and go to ebay... Because we're not getting that anal here. We just want a decent 4/5hp Tecumseh motor with the correct "look", and at a decent price.
So where do you get old Tecumseh flat heads? Well around here (Michigan), snow blowers are the donors. Winters in lower Michigan are pretty tame, but can be snowy, so snow blowers are A) common, and B) lightly used. Perfect donors. But with this in mind, you have to find the right motors (the right snow blowers.) Again I'm looking only for 4hp and 5hp Tecumseh motors. Tecumseh 3.5hp and lower won't work (they won't move my fat ass). Larger than 5hp won't work either (because of the lack of a HS motor size).
Edgers and leaf blowers are not ideal donors. Snowblowers are the best. why? the motors are just cleaner. No or little dirt to deal with (because they get used only during snow!) No air cleaners on snow blowers, because, well, why would you need one during the winter snow? It's pretty perfect for our purposes, with some modifications.
To get a Tecumseh 4 or 5hp, need to look for a snowblower in the 20" to 24" range. Wider than that and you'll be in the 6hp or larger range. Also personally i like old Craftsmen and Ariens models from the 1970s and 1980s. If they have points/condensor that's awesome, though not necessary. Pretty much any flat head until they get the "cyclone" style pull start (want the traditional 4 leg pull start, if possible.) Mind you the "cyclone" starter models are still good motors - they made these well into the 2000s. But the "look" isn't quite vintage (though the motors themselves are fine). We can 'fix' that look with older style decals later. So don't completely disregard these models, if one comes up for sale at a nice price.
Speaking of price, how much do these sell for? Well in the summer, snowblowers tend to be cheap. And older ones (not running) even cheaper. I've bought them from $10 to $75. Remove the motor, put the rest at the curb, and the metal scrapers get it and make it disappear!
Note you need to look at the PTO shaft on the motor. 3/4" is obviously the mini bike standard and what you want. A tapered PTO is the least desirable. 1" is also seen (and is OK.) but 3/4" is ideal. Don't worry if it's drilled or not. If it's a good motor and it's not 3/4" PTO, that's still OK, just a bit more work.
And i should mention that some snow blowers have a second small PTO (used for reverse often). No worries! Don't let a perfectly good motor pass if it has that. We can deal with it...
The one disadvantage to snow blower motors is the flywheels. It's steel and it's heavy. This is unlike "made for minibike" Tecumseh motors, that have an allow flywheel. This isn't a huge deal. I wish snow blower had the alloy flywheel, but they don't. It's OK though. It's not as big a deal as some may think.
I should also mention that i am by NO MEANS an expert on vintage Tecumseh flat heads. All i can tell you is what has worked for me (in the following posts.) There's a lot of compromises that will drive the "purists" crazy. I'm sorry about that. But here we go....
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