GT185 with GT250 motor swap?

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sandsz
On the street
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Joined: Mon Jul 14, 2014 8:01 am
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Suzuki 2-Strokes: 1976 GT185

GT185 with GT250 motor swap?

Post by sandsz »

Hello!

So I have a '76 GT185 that I tore down the motor and started pulling bearings from the crank to replace the middle, RH and LH seals. In my area I found a guy that is selling old suzuki rollers and he has a few GT250s.... since GT185 motor tear downs are pretty rare to come by I was looking at gt250 tear downs.

Interestingly almost everything looks exactly the same, inside and out. I noticed the few changes like divits on the bearings instead of pins to keep them still, etc.... but honestly the motors look almost exactly the same.

So my question is... could one install a GT250 motor on a GT185 frame? If I'm rebuilding a GT185 motor, honestly the procedure is most likely very much the same for the GT250. I could be wrong!
sandsz
On the street
Posts: 17
Joined: Mon Jul 14, 2014 8:01 am
Country: USA
Suzuki 2-Strokes: 1976 GT185

Re: GT185 with GT250 motor swap?

Post by sandsz »

I got a response from the dude: "Three frames, wheels, one engine is complete but no carbs, other engine is just a lower end. Pile of misc gt250 parts. 150 takes it all" $150 for a bunch of parts... that doesn't sound too bad to me then again it could be a cluster fart.

I know if I wasn't married I'd be driving to pick it up right now....
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tz375
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Re: GT185 with GT250 motor swap?

Post by tz375 »

It's the old "Anything is possible" story. I personally would be a little reluctant to put a heavier more powerful motor in that light chassis, but AHRMA GT185 racers probably make more power than that in a modified stock chassis.

It is probably one of those, "if you have to ask, maybe you shouldn't" things
sandsz
On the street
Posts: 17
Joined: Mon Jul 14, 2014 8:01 am
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Suzuki 2-Strokes: 1976 GT185

Re: GT185 with GT250 motor swap?

Post by sandsz »

True. I'm getting a HF 20 ton press soon to press out the con-rods and honestly I've "reconditioned" a few bikes but never split the cases before... no wait I did do a complete rebuild on a piaggio vbc 150. Now that I have split cases on the GT185 motor, I'm getting comfortable with the idea of reconditioning motors too. I know the gt185 is as simple as it gets and from what I saw the GT250 has almost no differences.

Yahhhhh I'm hemming and hawing on this one, I don't want to go down the path of "too many projects, can't find a place to start" road AGAIN. A few moves, a wife and two kids I finally got out of the weeds of "projects" by selling, giving away, scraping SO MUCH.

I really need to build a shop so I can *hide* these projects. :)
D&D CHASSIS
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Suzuki 2-Strokes: GT750 dragbike
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Re: GT185 with GT250 motor swap?

Post by D&D CHASSIS »

[quote="tz375"]It's the old "Anything is possible" story. I personally would be a little reluctant to put a heavier more powerful motor in that light chassis, but AHRMA GT185 racers probably make more power than that in a modified stock chassis.

Richard, that is the drag racers creed........
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ConnerVT
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Suzuki 2-Strokes: T500R (now), T500M (40 yrs ago)
Location: North of Albany, NY

Re: GT185 with GT250 motor swap?

Post by ConnerVT »

Hey, anything will work. Until it doesn't. :up: :wink:
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tz375
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Re: GT185 with GT250 motor swap?

Post by tz375 »

D&D CHASSIS wrote:
tz375 wrote:It's the old "Anything is possible" story. I personally would be a little reluctant to put a heavier more powerful motor in that light chassis, but AHRMA GT185 racers probably make more power than that in a modified stock chassis.

Richard, that is the drag racers creed........
And Road Racers, but we sometimes know what we are doing. Other times we'll take a calculated risk (calculated is a slight exaggeration, but we're not on the street and we are in the company of other performance geeks who provide a sanity check.
Vintageman
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Suzuki 2-Strokes: Suz, Yam, Honda, Kaw.
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Re: GT185 with GT250 motor swap?

Post by Vintageman »

Get the GT185 running: sell it.

Save a little more (wife doesn't need to know about your little $ stash) and strive to buy a complete low oxidized GT250. There are still a few out there and reasonable versus other vintage bikes

You'll be very happy and will have more time to enjoy life.
Current Bikes
74 GT250 (T350 upgrade),
76 GT250 (T350 upgrade),
71 T350,
70 T350,
74 GT380,
75 T500,
73 GT550,
75 GT750,
72 Yamaha DS7 (R5 upgrade),
77 Yamaha RD400 (Daytona Cyls),
sandsz
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Joined: Mon Jul 14, 2014 8:01 am
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Suzuki 2-Strokes: 1976 GT185

Re: GT185 with GT250 motor swap?

Post by sandsz »

That is good advice. The guy came back and said he also has two GT380s... All for $250. I think I've passed the stage of gather gather.... I think I'll follow the advice of getting the GT185 running and, if I feel like I want to go bigger, sell it. Sanity Check indeed!
sandsz
On the street
Posts: 17
Joined: Mon Jul 14, 2014 8:01 am
Country: USA
Suzuki 2-Strokes: 1976 GT185

Re: GT185 with GT250 motor swap?

Post by sandsz »

Ok ok I know I said that was it... but the more I look between the GT185 and GT250 cases and cranks, they look the same to me. I mean the gt250 is a 6-speed and obviously the jugs are bigger and they did away with the starter/generator and made the size case cover smaller.... but... man!
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