was cruising down the highway ~70 when the bike started losing power..heard what i thought was rocker or primary noise then it backfired through the intake and shut off. pulled over and it restarted but was running rough.
called for a tow and got her home.
i removed the outer primary cover and cranked the bike and its good on that side. I now believe the issue is in the engine but not sure on the next step. already pulled pushrod covers and checked each cylinder at TDC and I could spin them and the lock nuts were also intact.
it almost seems like its valve related. my next step is to remove the rocker box top to make sure the valve springs are intact.
any suggestions on the next step I should take.
2012 SG with ~17k on the 107 build.
I will take a short video to see if it helps but don't want to do any more damage than what's been done.

thanks

 

Next step would be a compression check.

 

i've done all the work on my bike but have never performed a compression or leak down check. looks like i will be learning something.
also don't have a compression gauge. will a harbor freight one suffice .

 

Yes a Harbor Freight unit will do .... Search YouTube for helpful videos ... Good Luck

 

Beware of HF compression testers. If they don't have the Schrader valve it will read like 60psi low.
A Pittsburgh they sell is the same way.
Here's a helpful YouTube video...

 

will this one work
Professional Petrol Engine Compression Tester Kit Set for Automotives and Motorcycles https://a.co/d/14EhmLW

 

We had one in our group have a similar issue (by the way you described it) ...
after several hour of troubleshooting ...found a bad crank sensor ....

but also sounds like a lifter may have failed ...(collapsed etc...)

hopefully it's not too serious !!!

good luck ....

 

You can rent a compression tester for free at the auto parts store.

Is your fuel pump running? Because your issue sounds fuel related from your description.

 

~209-210 front and rear
compression releases disconnected and tb propped open.

 

yes...fuel pump is running. bike will start and run. starts fine then starts to run rough.

thanks