After re-building the engine I´m ready to fire it up but I´m in trouble!!

BigBoreSwede

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Hello.

So...some of you might know I´ve been re-buliding my engine partly this winter.

Now it´s in the frame and I´m ready to fire it up but things ain´t going my way.

Here are the problems:

-Won´t start, only backfires occasionally. (Kickstart, no starter).
-It´s much more heavy to kickstart now then it was before the re-build.


Here is what I have done during the winter....more or less:

-New camchain guide and tensioner.
-New camchain (thight as hell)
-Lapped valves.
-New camshaft bearings.
-New valve stem seals.
-Carbs cleaned.
-Pistonhead and cumbustions chambers cleaned.
-New gaskets.


I do run 750cc with Boyer ignition (blue box) and I´ve set timing like this. Crank on "T" and trigger magnet right behind the peephole in the pickup plate. This should at least make it start.

I think I´ll drain it from oil and re-install the starter untill the engine is working OK.......my legs are very spongy by now:laugh: I´ll also take a second look at the carbs and fill the gastank fresh gas.


I know this type of questions are hard to answer but anyone have any idea. Maybe an engine that´s been apart always is hard to start??

/BigBoreSwede
 
First, I would check that the cam was installed and timed correctly. You can do so without taking much apart and with the motor still in the frame by following the instructions here .....

http://www.650motorcycles.com/CamTiming2.html

If that's OK, then I would play with your ignition timing setting. Try it a little to the left and right of where it is now. Maybe it's not quite close enough for it to start. As I understand it, the Boyer system can't be set accurately until the engine is running and you can use a timing light at something like 5K RPM.

As far as I know and from past experience, hard starting after a rebuild is not common unless you've done something wrong. All the rebuilds I've done started right up almost instantly. This includes other brands and other types of motors besides the 650.
 
Try retarding the ignition a bit, until its up and running and you can time it properly.

Agreed though, these 750-kitted engines are much harder to kick than the standard engine.

I.
 
i know mine's tough... bent kickstart lever tough... but yeah, double check the cam and ignition timing, sounds like mine when i got it back together, i used the wrong rotor mark and was off considerably. moral: don't time in the dark...
 
Thanks guys:thumbsup:

I was totally wrong. Did the timing with the crank lined up agains the "T" mark. Way out of line:banghead:

Today I did it again with the crank lined up at the "first" mark on the rotor and 3 kicks later it was running.

/BigBoreSwede
 
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