Best air cooled motor for conversion

Bultaco
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Bultaco 3/23/2014 6:29pm
3/23/2014 6:29pm
If you want to get technical….all engines are air-cooled. The question is whether you direct the air past cylinder fins or radiator fins.

There were some great 250cc air cooled engines between1978 and 1982. I'd be partial to the Honda or Kawasaki engine, but I suppose it would come down to parts and engine you could find for starters. I've spent some time riding a buddies 2001 KX 250. For the money he paid ($1500 5 years ago?) it is the cheapest fun any of us have in a long long time. We both keep commenting how much fun it is ride. Nice solid kick in the pants power.
Ing
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Ing 3/23/2014 6:46pm
3/23/2014 6:46pm
83 Husky 500. YZ490 would probably be better for parts though.
Bret
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Bret 3/23/2014 7:07pm
3/23/2014 7:07pm
cable wrote:
490 maico Smile
X2
BobPA
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BobPA 3/23/2014 7:15pm
3/23/2014 7:15pm
You mays well put an xr 400 engine in a modern crf chassis.









Extreme sarcasm

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wardy
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wardy 3/23/2014 10:24pm
3/23/2014 10:24pm
the reason a 490 maico motor worked so well was the torque it had. and it has to be a 1981 no other 490 matched it.

air cooled vrs water, best thing about that is the bike could cartwheel 5-6 times pick it up and take off without a cloud of smoke and coolant all over the place, biggest issue back then is if the bars where straight enough or not broke off.

for woods racing be kinda cool not to worry about a stick or rock through the radiator. but they got really hot and lost alot of power.

then again rebuilds were 150.00.
wardy
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wardy 3/23/2014 10:25pm
3/23/2014 10:25pm
indy_maico wrote:
[img]http://www.maicoonly.co.uk/images/thumbnails/1/900/maico_s1_490.jpg[/img] [img]http://www.maicoonly.co.uk/images/thumbnails/1/900/s1_250_maico13264680074f104ba73748f.jpg[/img] http://www.maicoonly.co.uk/maico-parts/engines.html




http://www.maicoonly.co.uk/maico-parts/engines.html
LOL kick starter on the side it was meant to be on! Smile
VET176
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VET176 3/23/2014 11:09pm
3/23/2014 11:09pm Edited Date/Time 3/23/2014 11:09pm
MR. X wrote:
What about the kdx 200 ,my buddy had a 84 i believe and that thing was so smooth and powerful. I think the exhaust came out...
What about the kdx 200 ,my buddy had a 84 i believe and that thing was so smooth and powerful. I think the exhaust came out of the cylinder at an angle too which might clear the down tube on a modern Al frame without a conversion.
X2

Would you be faster on a 490 or a 200 is the question.
Robgvx
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Robgvx 3/24/2014 3:41am
3/24/2014 3:41am
philG wrote:
84 RM500...... was an awesome engine just wasnt fashionable as everything was going water cooled , and it looked dated. Still the best sounding 2 stroke...
84 RM500...... was an awesome engine just wasnt fashionable as everything was going water cooled , and it looked dated.

Still the best sounding 2 stroke i ever had.
+1.

Best sounding bike ever apart from an RC500.
Tokyo_Tiddler
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Tokyo_Tiddler 3/24/2014 11:44am
3/24/2014 11:44am
TeamGreen wrote:
Thinking one of these motors...maybe? [img]https://p.vitalmx.com/photos/forums/2014/03/22/49005/s1200_image.jpg[/img]. That's a Newmann "sourced" gas-tank that looks BETTER than new. Now I understand how people build these bikes & DON'T...
Thinking one of these motors...maybe?

.

That's a Newmann "sourced" gas-tank that looks BETTER than new. Now I understand how people build these bikes & DON'T want to ride'em; so, I'll be running a different tank at the races.

Braaaaap!
The 1979 CR250 was one of the best stock air cooled engines ever. Loved that engine, hated the suspension.

mike
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TeamGreen 3/24/2014 11:49am
3/24/2014 11:49am
TeamGreen wrote:
Thinking one of these motors...maybe? [img]https://p.vitalmx.com/photos/forums/2014/03/22/49005/s1200_image.jpg[/img]. That's a Newmann "sourced" gas-tank that looks BETTER than new. Now I understand how people build these bikes & DON'T...
Thinking one of these motors...maybe?

.

That's a Newmann "sourced" gas-tank that looks BETTER than new. Now I understand how people build these bikes & DON'T want to ride'em; so, I'll be running a different tank at the races.

Braaaaap!
Tokyo_Tiddler wrote:
The 1979 CR250 was one of the best stock air cooled engines ever. Loved that engine, hated the suspension.

mike
The Swing-Arm is a POS, too...1980 or an After-Market is a must.
Tokyo_Tiddler
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Tokyo_Tiddler 3/24/2014 11:56am
3/24/2014 11:56am
TeamGreen wrote:
Thinking one of these motors...maybe? [img]https://p.vitalmx.com/photos/forums/2014/03/22/49005/s1200_image.jpg[/img]. That's a Newmann "sourced" gas-tank that looks BETTER than new. Now I understand how people build these bikes & DON'T...
Thinking one of these motors...maybe?

.

That's a Newmann "sourced" gas-tank that looks BETTER than new. Now I understand how people build these bikes & DON'T want to ride'em; so, I'll be running a different tank at the races.

Braaaaap!
Tokyo_Tiddler wrote:
The 1979 CR250 was one of the best stock air cooled engines ever. Loved that engine, hated the suspension.

mike
TeamGreen wrote:
The Swing-Arm is a POS, too...1980 or an After-Market is a must.
Exactly.. I bent 2 swing arms in '79.. they would twist when you landed from a big jump and derail the chain. Worst rear shocks of any bike I ever had so I went the Fox air shox route. Engine and handling were tops though.
FreshTopEnd
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FreshTopEnd 3/24/2014 12:12pm
3/24/2014 12:12pm
TeamGreen wrote:
Thinking one of these motors...maybe? [img]https://p.vitalmx.com/photos/forums/2014/03/22/49005/s1200_image.jpg[/img]. That's a Newmann "sourced" gas-tank that looks BETTER than new. Now I understand how people build these bikes & DON'T...
Thinking one of these motors...maybe?

.

That's a Newmann "sourced" gas-tank that looks BETTER than new. Now I understand how people build these bikes & DON'T want to ride'em; so, I'll be running a different tank at the races.

Braaaaap!
Those ally tanks were/are beautiful. I 've collected spares . . .
newmann
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newmann 3/24/2014 1:13pm
3/24/2014 1:13pm
TeamGreen wrote:
Thinking one of these motors...maybe? [img]https://p.vitalmx.com/photos/forums/2014/03/22/49005/s1200_image.jpg[/img]. That's a Newmann "sourced" gas-tank that looks BETTER than new. Now I understand how people build these bikes & DON'T...
Thinking one of these motors...maybe?

.

That's a Newmann "sourced" gas-tank that looks BETTER than new. Now I understand how people build these bikes & DON'T want to ride'em; so, I'll be running a different tank at the races.

Braaaaap!
FreshTopEnd wrote:
Those ally tanks were/are beautiful. I 've collected spares . . .
I used to have a spare....Laughing

One day when I figure out what I need, maybe Team Green will have some spare titanium hardware laying around.
newmann
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newmann 3/24/2014 1:24pm
3/24/2014 1:24pm
Speaking of spares.....and swing arms, look what showed up after 22 months.

Matt Fisher 3/24/2014 2:49pm
3/24/2014 2:49pm
philG wrote:
84 RM500...... was an awesome engine just wasnt fashionable as everything was going water cooled , and it looked dated. Still the best sounding 2 stroke...
84 RM500...... was an awesome engine just wasnt fashionable as everything was going water cooled , and it looked dated.

Still the best sounding 2 stroke i ever had.
wow123 wrote:
Along those lines few years ago I had an 82 465 and put last gen "right side up" cr250 forks on it, rebuilt the shock and...
Along those lines

few years ago I had an 82 465 and put last gen "right side up" cr250 forks on it, rebuilt the shock and linkages.

Very good motor in an agile chassis, quite light too, was a blast to ride

Wonder what was the lightest production air cooled 500?
Benchracer17 wrote:
not to be "that guy", but the '81 YZ was a 465 & the '82 was 490

get your years straight, dammitLaughing
/sarcasm
Well, Yamaha did make a 82 465, the IT465.... Laughing
neverwasfastenuf 3/24/2014 5:35pm
3/24/2014 5:35pm
newmann wrote:
Speaking of spares.....and swing arms, look what showed up after 22 months. [img]http://i609.photobucket.com/albums/tt171/duc-man97/IMG_20140324_131218_557_zpsa69fcda5.jpg[/img]
Speaking of spares.....and swing arms, look what showed up after 22 months.

It's like Christmas every frikkin month at your place!
neverwasfastenuf 3/24/2014 5:38pm
3/24/2014 5:38pm
cable wrote:
490 maico Smile
Oh yeah can't go wrong with the Maico 490, an 84 CR 500 wouldn't be too bad though.

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GuyB
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GuyB 3/24/2014 5:40pm
3/24/2014 5:40pm
The Rock wrote:
What is the best air cooled motor from the past to stick into a current day chassis? I am thinking they would have to be lighter...
What is the best air cooled motor from the past to stick into a current day chassis? I am thinking they would have to be lighter than a water cooled motor and would be perfect for a 15 to 20 minute moto weapon.
SRP33 wrote:
PW 50
With Slaterskins.
Tumblin
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Tumblin 3/24/2014 7:11pm
3/24/2014 7:11pm
might as well stuff an XR600 in there just to make 'em go hmmmm?
The Rock
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The Rock 3/25/2014 12:38am
3/25/2014 12:38am Edited Date/Time 3/25/2014 12:49am
newmann wrote:
Speaking of spares.....and swing arms, look what showed up after 22 months. [img]http://i609.photobucket.com/albums/tt171/duc-man97/IMG_20140324_131218_557_zpsa69fcda5.jpg[/img]
Speaking of spares.....and swing arms, look what showed up after 22 months.

I for sure wouldn't use that shipping carrier again.

This project bike would be complete with a air cooled 300cc KTM cylinder. I know people make water cooled after market cylinders out the yin yang but who can make a finned cylinder?

Just taking a WAG at the weight but can you imagine a 210 pound 300cc two stroke? Just taking a WAG at the weight. Speaking of weight anyone have the weight of two KTM radiators hoses fluid water pump and cap? A finned cylinder's fins couldn't possible add on that much weight over an water cooled cylinder could they? I have to believe there would be a weight savings and what weight remains would be centralized instead of hanging off the sides of the bike like radiators do.
TooOldToPlay
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TooOldToPlay 3/25/2014 8:06am
3/25/2014 8:06am Edited Date/Time 3/25/2014 8:08am
newmann wrote:
Speaking of spares.....and swing arms, look what showed up after 22 months. [img]http://i609.photobucket.com/albums/tt171/duc-man97/IMG_20140324_131218_557_zpsa69fcda5.jpg[/img]
Speaking of spares.....and swing arms, look what showed up after 22 months.

neverwasfastenuf wrote:
It's like Christmas every frikkin month at your place!
I'm assuming those are some of Karl's creations...if so..when you get a minute, would you mind pulling the plastic off and posting up a photo or two of those gems? Thanks!
Madmax31
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Madmax31 3/25/2014 8:19am
3/25/2014 8:19am Edited Date/Time 3/25/2014 8:22am
I've ridden a lot of bikes beginning in 1977. I'd always heard how great the Maico 490 motor was but really doubted it. I mean how could an old chain driven primary, no power valve, cobby appearing, Bing carb'd motor really be any good at all, much less the "best". I can tell you it's absolutely amazing. Smooth yet amazingly fast, broad, you name it. It's the sh*t.

Not sure how much it weighs, but it's an amazing motor.
1
Cygnus
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Cygnus 3/25/2014 8:50am
3/25/2014 8:50am
Old XR 250 or XL 350's would be a fun ride. Kinda like the 250f engine in the cr85 roller that service hinda does.
newmann
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newmann 3/25/2014 9:35am
3/25/2014 9:35am
newmann wrote:
Speaking of spares.....and swing arms, look what showed up after 22 months. [img]http://i609.photobucket.com/albums/tt171/duc-man97/IMG_20140324_131218_557_zpsa69fcda5.jpg[/img]
Speaking of spares.....and swing arms, look what showed up after 22 months.

neverwasfastenuf wrote:
It's like Christmas every frikkin month at your place!
TooOldToPlay wrote:
I'm assuming those are some of Karl's creations...if so..when you get a minute, would you mind pulling the plastic off and posting up a photo or...
I'm assuming those are some of Karl's creations...if so..when you get a minute, would you mind pulling the plastic off and posting up a photo or two of those gems? Thanks!
Here is a pic of the first one.

Matt Fisher 3/25/2014 11:16am
3/25/2014 11:16am
The Rock wrote:
I for sure wouldn't use that shipping carrier again. This project bike would be complete with a air cooled 300cc KTM cylinder. I know people make...
I for sure wouldn't use that shipping carrier again.

This project bike would be complete with a air cooled 300cc KTM cylinder. I know people make water cooled after market cylinders out the yin yang but who can make a finned cylinder?

Just taking a WAG at the weight but can you imagine a 210 pound 300cc two stroke? Just taking a WAG at the weight. Speaking of weight anyone have the weight of two KTM radiators hoses fluid water pump and cap? A finned cylinder's fins couldn't possible add on that much weight over an water cooled cylinder could they? I have to believe there would be a weight savings and what weight remains would be centralized instead of hanging off the sides of the bike like radiators do.
There are adhesives that hold airplanes together, so I would imagine they could be used to "stick" pre-made fins on a cylinder.
captmoto
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captmoto 3/25/2014 11:17am
3/25/2014 11:17am
What are those swing arms going on?
Suns_PSD
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Suns_PSD 3/25/2014 11:35am
3/25/2014 11:35am
Modern KTM 300 engine. Machine the water ports off the cylinder and head and attach fins somehow to turn it aircooled.

Air-cooled motors are a romantic notion, right up until you feel the massive power loss after 10 minutes of riding on a TX summer day.

My feeling is if you had a known good air cooled engine on the shelf, this project would make since.

Good Luck.
newmann
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newmann 3/25/2014 12:17pm
3/25/2014 12:17pm
captmoto wrote:
What are those swing arms going on?
One of them is going on my 159 pound 76 CR125 lite bike project.



Another is going on my DG Team replica.





And the other is for a buddy of mine here in Texas.
vintagedave393 3/25/2014 12:40pm
3/25/2014 12:40pm
Maicos and CR480s, while the best open class powerbands, are problematic in new chassis because they had right side countershafts. A 1981 RM465 with a 5 speed would be a good candidate. The 82 thru 85 models were 4 speeds.
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