How-to video for J-Engine Big Bore now on Youtube

This is not a complete or flawless instructional video - although you may get all the info you need from it if you have some experience with engine repair.It was done in a parking lot of our hotel because as long time friends of this channel may recall - Royal Enfield threatened my dealer with revoking his license if he allowed videos to be made in his workshop (actually they threatened him in case the existing vids where not removed but never followed up on that threat). So I grabbed my favorite mechanic on his day off and we got the ball rolling. Yes, the bike is super dirty, the washing facility in the shop does not work since weeks (this is India) and I had no idea of the extend of dust under the various covers. Also: we had used the head gasket from the 410cc Big Bore and when fire up the first time the piston made an audible sound so we had to re-do the entire thing after we widened the gasket to the size of the 500cc piston. After installation of the piston we also did the Powertronic V4 but that process is sufficiently explained in their manuals and needs no extra video IMO. However, the 500cc will NOT run properly with cutouts, stalling at low rpm and less power UNTIL the mapping is done right. After a few trial runs I used a slightly modified map from my Euro5 Himalayan V4 Powertronic that worked quite nice. There is still knocking when accelerating sharply so timing needs adjustment but I'd say its 80-90% correct - not bad for not having a dyno to check.

Total time for the cylinder change: 1h30min.
 
When undoing the Head he appears to just rip into it with no sequence, does the Manual call for a Sequence?
The Cam Alignment Tool being used would be a Copy I am guessing and next to useless when the Crank is not set at TDC which wasn't shown.
From the gaps either side of the Cam bolts compared to when removed, the installation would have Retarded the Cam timing but as TDC isnt determined then perhaps it is actually correct due to factors unseen.
:unsure:
 
You have a point, there was intense juggling with the piston position which I did not gauge to be important so left out from the video. I guess those are the "factors unseen". The bike ran quite well after initial startup minus the flaws attributed to the missing ECU adjustment. I guess all was done right - simply because now the engine run very well except some knocking and some small hickups when cold (but no stalling).
Regarding sequence: I have also learned it is important, but never seen a mechanic here (any mechanic in any workshop) following that particular ritual.
 
The Manual at 5.5.35 shows the Criss Cross pattern for doing the Bolts.
And 5.8.35 informs us that the Head bolts are to be torqued to 12-18Nm that must be wrong , Himalayan is 40 to 45.
Manual also states that the Head and Cam bolts are "single use":cool:🙃
 
Intense juggling was most likely getting TDC from the "rock".
Strange the Manual mentioned the tool that locates the Crank position but it is not listed in the Special Tools list :confused:
 
Your tech must have a universal joint in his wrist 😎 , he is very good with the Tee Bar.
 
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