ROTAX 185 cc, 2-cycle 9HP Engine from Wajax "Pacific Pumper Mark 3" Fire-Fighting Rig

[chazdaddy]

I bet these engines are never rebuilt, probably take a lot and abuse and last forever. Of course, after someone hops it up for racing, that's when the trouble starts LOL's.

Pull the pump housing and have a look see at the PTO. May have a weird end that won't take a clutch, if so you may be done. :shrug:

If you like 2cycles, there are some really good old kart engines out there for not much. You can get them for maybe $200 or less and used to be able to rebuild for $300. They generally make approx 15hp plus or minus. One problem, need expensive clutch to run.

I see them on cl and ebay from time to time. Watch for these 100cc piston port engines: Komet K-71, TKM BT-82, Yamaha KT-100. There are also other piston ports, reed valve, rotary valve up to 135cc. Some are starting to become vintage, so prices are getting too high to mess with.

I have 6 TKM BT-82's, some running some not.

TKM BT 82 116cc Go Kart Engine Blueprinted Fast Runs Great Reliable Motor | eBay

 

[MoTo-BunnY]

More great info! thanks guys....I hope to wrap up my van project today (installing a "headache rack" in my 1973 GMC Vandura-have to while the weather is still good, it won't fit in the garage!) and then back to minibikin'!

I will take that pump flange off, for sure, been meaning to.....then I will put the stock carb back on and see if I can get it started! :thumbsup: can't wait for that angry bees in a can sound! :biggrin:

 

[bikebudy]

Best of luck

 

[MoTo-BunnY]

Best of luck

Thanks! I think it will run....it seems to be in good shape, I have already squirted oil into the plug hole and turned the engine over no problem. Hopefully the decompression thingy isn't stuck OPEN. The only worrisome thing is the carb, as it was stored by someone with no air filter or cover and was pretty grubby.

I wish I could tinker with it right now but alas, it is too nice out. . ..will report back as soon as I can though....... :thumbsup:

thanks again everyone for the help and suggestions on this engine....I'm a newbie to 2-strokes but they sure look and sound fun!

 

[bikebudy]

Sent you a PM you need to check out

P.s. From what I could see in photo, the decompression valve is closed

 

[Boomstick]

Tecumseh float carb should work fine, as a gravity feed carb.

Otherwise, you would still need a external fuel pump if the tank were lower than the carb.

Also don't think a 2 stroke don't have power

These are 2 stroke

Polaris Snowmobile Engine Powered Kawasaki Asphalt Drag Bike @ Dragway 42 - YouTube


I would love to see that pump end pulled off the engine and see the crank shaft end?

I never doubted 2 smokers having power. I just have found with the 2 stroke bikes I had, it's power in all the wrong places. One second you're screaming obscenities at it while trying to get up an incline from a dead stop, and the next you're hanging on for dear life once it finally gets on its feet.

2 strokes are good if you want to ride the thing balls to the wall ALL of the time.

I prefer something I can just putter around & cruise on. That's just my preference though.

 

[bikebudy]

Any fire in that Dragon ?

 

[MoTo-BunnY]

Any fire in that Dragon ?

I didn't get much time to work on it today, still wrapping things up outside on my van projects, while the rain is still holding off.

However, I did get a little time in on the ol'Rotax and I was able to, after MUCH effort, get the pump mounting flange off. I used a large puller and a bunch of PB Blaster, and tapping on the wrench on the end of the puller, with a brass sledge. The repeatedly taps steadily turned the puller until finally, with a loud pop, the flange and puller jumped towards me! Here is the immediate aftermath:

Then, after a few slugs of congratulatory beer, :drinkup: I measured the shaft dimensions. (that's what SHE said!)

It's a bit shorter than I would like at 1.6565 in. or 1 21/32 (42mm).

The shaft has two diameters, the larger back half and the smaller front half.

Here is the larger diameter at .619 in. or 5/8 in (15.7mm).

Here is the smaller diameter threaded part at .4705 in. or 15/32 (12mm)


Here is the :cursing: &%)$%*!?!! woodruff key that had a bit of rust on it and REALLY wanted to hold on to that flange mount!

I will probably get some time on the engine tomorrow and hook the carb back up. Hopefully, I will have time to try and start it too, but not if I end up working late like tonight (too noisy for the neighbors). We will see. . . .that's it for the after-action report for now, I'm off to bed, pretty beat.......... :sleeping:

 

[bikebudy]

That crank end is not the best news but, you can work with it.

 

[toomanytoys]

I never doubted 2 smokers having power. I just have found with the 2 stroke bikes I had, it's power in all the wrong places. One second you're screaming obscenities at it while trying to get up an incline from a dead stop, and the next you're hanging on for dear life once it finally gets on its feet.

2 strokes are good if you want to ride the thing balls to the wall ALL of the time.

I prefer something I can just putter around & cruise on. That's just my preference though.

Riding a 2 stroke bike takes skill. Lots of it. I never was the best at it. I did good on 2 stroke 4 wheelers.

You shift, constantly. You slip the clutch, you rev the piss out of it, and hang on. A properly operated 2 stroke will out pace a 4 stroke any day. It requires a lot of practice.

I rode a KX100 for a few years, and it took me a lot of practice to get it right. But once I did, oh my.

Saying that I am not a big 2 stroke fan. I love the sound, I love the easy rebuilds, but these days I don't have the guts to hang on.

 

[MoTo-BunnY]

That crank end is not the best news but, you can work with it.

That's kinda what I thought. . .like having to put the clutch on gear side out to line up right with a rear sprocket?

I'm surprised it was 5/8 on such a powerful engine-I would have thought it was 3/4"? :shrug: Bummer in a way as that means no Downs Bros. manual clutch, which would have been ideal on a drag mini....at least until if & when they come out with a 5/8 version?


On a related note, here is a drag-mini frame I am looking at that I really like:

NITRO 44 Mini Drag Bike ROLLING CHASSIS

 

[Boomstick]

Riding a 2 stroke bike takes skill. Lots of it. I never was the best at it. I did good on 2 stroke 4 wheelers.

You shift, constantly. You slip the clutch, you rev the piss out of it, and hang on. A properly operated 2 stroke will out pace a 4 stroke any day. It requires a lot of practice.

I rode a KX100 for a few years, and it took me a lot of practice to get it right. But once I did, oh my.

Saying that I am not a big 2 stroke fan. I love the sound, I love the easy rebuilds, but these days I don't have the guts to hang on.

Like you, I rode two stroke bikes for a while. I had a KX500 that was an absolute monster. I was never a real hot rod, but I wasn't any slouch either.

I just hated hanging onto the thing once it woke up. It was scary fast, and once it got on its feet, I'm pretty sure it could outpace some sportbikes. But, again... it was all top end.

I prefer running around with a 4 stroke. It's so much nicer to ride. :thumbsup:

 

[bikebudy]

I had a Hirth engine like this one, in a 444 Husky.

Unique feature to the engine is, it will run in ither direction ! All you need to do is start it the other way !

Used to be able to shut the Husky off, wrap a rope around the clutch, start it the other way and then back up ! !

 

[MoTo-BunnY]

I had a Hirth engine like this one, in a 444 Husky.

Unique feature to the engine is, it will run in ither direction ! All you need to do is start it the other way !

Used to be able to shut the Husky off, wrap a rope around the clutch, start it the other way and then back up ! !

Oh wow, crazy! I saw something about that during my crash course in 2-strokeology, on googling around. I was wondering why that blank was on the opposite hole on the recoil starter, looking like it could be installed to pull and rotate in either direction! :thumbsup:

 

[Neck]

Yup, a two stroke will run in either direction, but to make it run right in the opposite direction, the spark timing must be adjusted.

 

[rmm727]

So what about those golf kart 2 strokes that do start either way? Is the timing just off in reverse?

 

[bikebudy]

They have a floating timming plate controlled by cable when you shift to reverse it retards the timming. Ski-Doo did the same thing with a 1cyl Rotax snowmobile, I don't recall the model.

 

[Boomstick]

Actually, do you think you could fab up a bracket & run a helical gear from the crank, to a jackshaft?

That might give you a little more wiggle room, and should be a fairly easily contained unit.

 

[Teamrosko]

I didn't get much time to work on it today, still wrapping things up outside on my van projects, while the rain is still holding off.

However, I did get a little time in on the ol'Rotax and I was able to, after MUCH effort, get the pump mounting flange off. I used a large puller and a bunch of PB Blaster, and tapping on the wrench on the end of the puller, with a brass sledge. The repeatedly taps steadily turned the puller until finally, with a loud pop, the flange and puller jumped towards me! Here is the immediate aftermath:

Then, after a few slugs of congratulatory beer, :drinkup: I measured the shaft dimensions. (that's what SHE said!)

It's a bit shorter than I would like at 1.6565 in. or 1 21/32 (42mm).

The shaft has two diameters, the larger back half and the smaller front half.

Here is the larger diameter at .619 in. or 5/8 in (15.7mm).

Here is the smaller diameter threaded part at .4705 in. or 15/32 (12mm)


Here is the :cursing: &%)$%*!?!! woodruff key that had a bit of rust on it and REALLY wanted to hold on to that flange mount!

I will probably get some time on the engine tomorrow and hook the carb back up. Hopefully, I will have time to try and start it too, but not if I end up working late like tonight (too noisy for the neighbors). We will see. . . .that's it for the after-action report for now, I'm off to bed, pretty beat.......... :sleeping:

Did you ever find a clutch to fit the rotax 185 from the wajax

 

[MoTo-BunnY]

Did you ever find a clutch to fit the rotax 185 from the wajax

No, not yet, still working on carburetion issues on it at the present. I am considering trying to get an extension piece of some sort machined to extend the shaft for clutch use. :thumbsup:

I should be getting back to this engine soon as I now have a really cool Bonanza frame that it fit in nicely and make for a cool bike.