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Modifications from Type 2 to Type 1

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Joshes Member
Posts: 29
Joined: Sun Dec 02, 2007 2:41 am

Modifications from Type 2 to Type 1

Post by Joshes » Tue Jan 29, 2008 8:42 am


I'm new to the Honda 305. I recently purchased Type 2 CP77 305cc. I think this is 360 where both pistons works at the same time. I wonder if I can change to Type 1 180 where the pistons works simultaneously.

In short - I'd like to change my engine from Type 2 CP77 to Type 1 CB77 (without buying a new engine). Is this possible? Any parts I need to purchase to make this happen?

Please - I need as much information as I can.

Many thanks,

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davomoto Member
Posts: 2508
Joined: Sat Nov 18, 2006 7:36 pm
Location: Marin County CA

Post by davomoto » Tue Jan 29, 2008 3:34 pm

Welcome to the forum Josh! Are you sure it's a type 2 engine? Only one set of points? The pistons move up and dowm together? The main differences are the crank, the cams, and the points plate, so all of these parts would need to be replaced. You could grind the alignment post on the cam, and realign the cams 180 degrees apart to reuse old cams. Hope this helps!


CliffC Member
Posts: 256
Joined: Sat Jan 13, 2007 3:52 pm
Location: Roseburg, Oregon

Post by CliffC » Tue Jan 29, 2008 6:54 pm

Hi Joshes, Welcome to the forum. Its been a long time but I thought all CP's were Type I's. Like Davomoto said if its got two sets of points and two coils its a Type I. You can also pull the plugs and at TDC if both pistons are at the top it would be a Type II. CliffC

P-Town Mike Member
Posts: 8
Joined: Wed Oct 12, 2005 11:04 pm

type2 vs type 1

Post by P-Town Mike » Thu Feb 07, 2008 12:38 pm


I have all the parts you will need and am willing to trade for anything that you might have that is interesting!!!!! contact me at

p-town mike

dickinraleigh Member
Posts: 19
Joined: Wed Feb 06, 2008 12:27 pm
Location: Knightdale (Raleigh) NC USA

Type 1 to type 2 conversion

Post by dickinraleigh » Thu Feb 07, 2008 12:56 pm

If I remember correctly. The pistons for the CB/CL77 are different from the CA77. The differences are the piston tops. CB/CL is higher compression. I had a Superhawk with a Dream engine installed. I like the sound to the Dream engine's exhaust. Sounds like a Triumph.
Dick in Raleigh

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