Firing order?

[camos]

My valve adjustment project is turning into somewhat of a saga. I was using the procedure in the Tech Library article written by Goose for the gen 2 which indicated the firing order was 1-3-2-4. My gen 1 manual states the firing order is 1-3-4-2. I did not notice the discrepancy for a while though. Thought these engines were the same.

 

Oh well, there are no plans for me to give up my current job to become a mechanic so it probably doesn't matter all that much.

[abusive throttle cranker]

I ran into much the same problem. I eventually discovered that we do NOT use the firing order in setting the valves. Set your crank at TDC for #1; then 180* and do #3. Then the 180* plus 70* to TDC for #2 (yes there is a mark on the flywheel). After that then 180* to #4.

[dingy]

Firing order is the same for the 1983-2013 V4's, 1200/1300cc, used in all Ventures & Vmax's.

 

1-3-2-4 is consistent through 4 manuals I looked at.

 

1st picture is 1st Gen Ventures, 2nd is 1st gen Vmax's, 3rd is RSV's & 4th is Royal Star.

 

Given the 'V' configuration of the cylinders and the 2 throw construction of the crankshaft it would not be possible to alter firing order without different cams. One of the performance enhancers often mentioned is the installation of VMax cams in other V4's. This would not work across the family of bikes if the firing order were different.

 

Gary

[camos]

Firing order is the same for the 1983-2013 V4's, 1200/1300cc, used in all Ventures & Vmax's.

 

1-3-2-4 is consistent through 4 manuals I looked at.

Well, my manual says the firing order is 1-3-4-2. As far as I can tell it is the official Yamaha paperback manual. In any case, I am in the process of doing it as SemiRetired mentioned, which also coincides with the procedure as outlined by Goose.

 

Nice to have confirmation.

Thanks to all for the replies.

 

Edit:

Just in case there is any doubt I added a pic of the offending information from the manual.

Edited April 7, 2013 by camos

[Peder_y2k]

Looking closely, the manual pages indicate BOTH

FIRING ORDER 1-3-4-2

VALVE ADJUSTING ORDER 1-3-2-4

However, if we look closer, all the cam degree diagrams agree indicating that the actual firing order is 1-3-2-4

IMHO, I agree that the manual is incorrect in the text portion that indicated the 1-3-4-2

I followed the 1-3-2-4 sequence and it worked perfectly. I since changed my manual by crossing out the error and writing in the correct 1-3-2-4

-Pete, in Tacoma WA USA

'83,88

Edited April 8, 2013 by Peder_y2k
misspelling - bad machine

[MiCarl]

It's 1-3-2-4. There is a misprint where it is listed in Dingy's second figure.

 

If you think about it, the only way it could be 1-3-4-2 would require a much more complicated crank and wider engine.

[tommyp61]

Has anyone hooked up a degree wheel? How does one figure the exact number of degrees from one cylinder to another? I would like to know how a degree wheel is placed on the motor.

[dingy]

It's 1-3-2-4. There is a misprint where it is listed in Dingy's second figure.

 

If you think about it, the only way it could be 1-3-4-2 would require a much more complicated crank and wider engine.

 

Didn't see the misprint before. I was looking at the graph.

Gary

[abusive throttle cranker]

Tommy- I've done some research about degree wheels. Years ago a non- mechanic friend bought himself a Triumph. As I understand it a degree wheel is usually intended for a specific machine. It keys into the driveshaft there being a keyway intended for the flywheel or some such. Then its just a matter of marking the case- if there isn't an OEM mark. There are general purpose degree wheels but again- they must be set in relation to TDC or some exact marker.

[MiCarl]

You don't need a degree wheel to check valve lash, the angles aren't that critical.

 

If you're not comfortable eyeballing them you can borrow a protractor from someone's school bag and mark the alternator rotor with a pencil at 70, 180 and 250 degrees (there is already a mark at 0).

 

Working in order with cylinder 1 at TDC (0 degrees):

 

0 degrees - #1

180 degrees - #3

70 degrees - #2

250 degrees - #4