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Workshop => Engine and Bottom End => Topic started by: Nearman Creek on July 01, 2021, 10:33:18 PM

Title: Is there anyway I could tell the difference on what year of the engine I have?
Post by: Nearman Creek on July 01, 2021, 10:33:18 PM

Is there anyway I could tell the difference on what year of the engine I have? I don’t know if I have a 86 (short rod stroke) or a 87, 88, or an 89 motor. If I can’t tell the difference what’s the easiest way to figure out if I need a spacer plate or not?

Title: Re: Is there anyway I could tell the difference on what year of the engine I have?
Post by: croat1 on July 02, 2021, 08:17:02 AM

Is the engine still assembled and in the quad?

Joe

Title: Re: Is there anyway I could tell the difference on what year of the engine I have?
Post by: evaneyeball on July 05, 2021, 11:59:40 PM

If the cylinder is off one easy way to tell is that the year its made is stamped on one of the cylinder skirts on the bottom if not then the serial number on the left side near the front sprocket and shifter changes from year to year I believe I'm not sure of what the changes are though

Title: Re: Is there anyway I could tell the difference on what year of the engine I have?
Post by: dp250r on July 08, 2021, 06:56:52 AM

Short rod cylinder doesn't have a bridged intake first pic. 87 -89 long rod has bridged intake second pic.

Title: Re: Is there anyway I could tell the difference on what year of the engine I have?
Post by: atvmxr on July 08, 2021, 11:19:36 AM

only if its never been taken apart.  With a motor ~35 years old it could have any combination of cylinder, cases, crank, and transmission in it by now.  You need a spacer plate when using the 87+ crank (long rod) and the 85-86 piston, regardless of which style cylinder you have.  And then there are several set ups with aftermarket cranks/cylinders that may or may not require a spacer plate