Topic: Timing Issue?

[750K5]

 So I am at struggling with some new issues and thought maybe someone has had a similar experience. I thought I had my bike dialed and left town for work, I returned and its not running worth a darn. Last weekend I went through and set static timing and strobe timing (followed this procedure  http://www.hondachopper.com/garage/carb_info/timing/timing3.htm and Hackaweek) all sounded and seemed good. Well fast forward and I fire the bike upon my return and it sounds rough and is popping a bit. I went back to inspect the points plate to see if I left an adjustment loose, and threw the light on it and it's way out. last week it idled directly on the F mark and a throttle blip to approx 2500 rpm it landed on center of the advance marks. This was true for both 1-4 and 2-3.  So yesterday I decided to start over. I checked the points gap, attempted to set up static w my meter one cable to engine case the other to blue / 1-4. I turned the crank and the points open well ahead of the F mark when I try to adjust the plate I run out of adjustment on the plate and am still not able to get it corrected. The closest I get is near the advance marks over the stamped 1-4. I hope my description is understandable. So the question I have 1. Is it possible that the cam chain jumped time maybe its off one tooth? I went through the cam timing set up process w the help of HondaMan's book and the manual. The bike has been running descent from the first start. I'm stumped as to what could have changed. Any thoughts or similar experience would be appreciated.
Thank You

[Tim2005]

Has the advance unit stuck in the fully advanced position?

[750K5]

Has the advance unit stuck in the fully advanced position?

The Spark advancer is clean and free moving. I replaced with another I had that has the same orientation and looks to be the same style. I am getting the same results.

[Tim2005]

are the 2-3 points still timed correctly?

[750K5]

are the 2-3 points still timed correctly?

Seem to be the same degree out. I'm going to go back through valve lash and tensioner adjustments. Make sure nothing changed. I'm heading home to look into it now. Hopefully its something simple I'm overlooking.

[Tim2005]

I don't see how valve lash would affect it, on the 750 the points are on the end of the crank, ignition timing can be set without the cam installed even. This is a 750/4?

[750K5]

I don't see how valve lash would affect it, on the 750 the points are on the end of the crank, ignition timing can be set without the cam installed even. This is a 750/4?

It's a 750k5. You are correct. I'm just double checking my set up before I go back to static timing. It's almost like the advancer shifted somehow.   

[evinrude7]

have you checked the points gap again before trying to time it?

[bryanj]

There is so much "slop" in the system that moving the plate can alter the points gap by a large amount, gap should be 0.35mm to be exact and it takes a lot of messing to get both the gap and static toming spot on

[750K5]

There is so much "slop" in the system that moving the plate can alter the points gap by a large amount, gap should be 0.35mm to be exact and it takes a lot of messing to get both the gap and static toming spot on

I got it figured out.  I ended up replacing the spark advancer and the points plate. I had spare parts in the bin. The points are in much better shape and the contact surface is flat, the others were worn at an angle. I also had time to regroup as I was pretty irritated yesterday. I appreciate all the help and brainstorming. Tomorrow I'll revisit the carbs and check sync again.
Thanks again