Difference in Crankshaft Assembly for different years?

Need some help? Put your question up here. Many years of experience on the board to help you get up and running.

Moderators: oldjapanesebikes, H2RICK, diamondj, Suzsmokeyallan

Post Reply
Robiet
On the street
Posts: 20
Joined: Wed Jan 21, 2015 11:35 am
Country: United States
Suzuki 2-Strokes: 1972 GT380 1966 B100p RM80B

Difference in Crankshaft Assembly for different years?

Post by Robiet »

Hello, I am trying to find out if a 1974 gt380 crankshaft assembly will fit into a 1972 engine. Anyone have experience?
Craig380
Expert racer
Posts: 1254
Joined: Mon Dec 01, 2008 2:52 am
Location: Manchester, UK

Re: Difference in Crankshaft Assembly for different years?

Post by Craig380 »

The Suzi parts manual (http://www.oldjapanesebikes.com/mraxl_G ... /index.php) shows different model numbers for the J model and K model crank assemblies, but the L/M/A/B cranks are ALL the same part number.

However I've no idea if they can be swapped as an entire assembly.
1976 GT380 - wounded by me, and sold on
2006 SV650S - killed by a patch of diesel and a kerb in Feb 2019
2017 SV650 AL7 - naked and unashamed
rngdng
AMA Superbike
Posts: 1769
Joined: Tue Oct 14, 2008 6:47 pm
Location: Blythewood, SC, USA

Re: Difference in Crankshaft Assembly for different years?

Post by rngdng »

On the GT750, the cranks are slightly different (rods, actually), but the whole unit can be used as long as you match the pistons with the rods. Sooo, if you use a 76 crank, be sure to use the newest pistons. If you use a 72 crank, use the older pistons.


Lane
If you stroke it more than twice; you're playing with it.

Too many bikes, too much time, ENOUGH SPACE, FINALLY! Never enough money.........
User avatar
tz375
Moto GP
Posts: 6212
Joined: Mon Nov 03, 2008 10:47 am
Location: Illinois

Re: Difference in Crankshaft Assembly for different years?

Post by tz375 »

Lane is correct.

There were several changes in crankcase and cranks on the 750 and the issue of interchangeability on a 750 relates to wherether the thrust washers were on the big end or small end. Any crank will physically fit any year cases.

I don't know much about the 380 but suspect they are interchangeable.
Robiet
On the street
Posts: 20
Joined: Wed Jan 21, 2015 11:35 am
Country: United States
Suzuki 2-Strokes: 1972 GT380 1966 B100p RM80B

Re: Difference in Crankshaft Assembly for different years?

Post by Robiet »

Thanks for the info guys. I have a crank coming from a bike that had 4k on it. It ran well but was wrecked. The guy said that the seals were soft and tight on it. For the price, I took a chance. I'm going to rebuild mine myself but wanted another just in case something goes terribly wrong!!! The rod kits are in the mail. I will post detailed pics of that rebuild.
Post Reply