Head Mods for Combustion Chamber

It is messy. :)
Best done outside.
 
Depends on the length of the chain, like how old and stretched.
OK, so with only 5000kms on the clock, maybe unlikely. I suppose I could go with a second gasket and some modest material removal. I was looking and getting the aluminium section 3d printed and it isn't that expensive... I could get a 0.5cm one done and with the second gasket, that should be ok
 
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Is this intended or should I smooth it out ?
 
this intended or should I smooth it out ?
definitely not intended. I scanned a gasket and then used corel to smooth the edges but of course - nobody is perfect. on the other hand it hardly makes a difference at that size.
I have to agree with @Dool. Your chain is way too new. we did this with a Himalayan with 30k km and it just worked, I used a copper plate then, cant remember the thickness - but on the other hand 30k km is the time when at least for the BS3 version, a chain replacement was suggested by the technical manual (50k km from BS4 onwards).
 
Today if I had to do it again I would go the dremel way. I know @Dool did a master piece with it but to avoid knocking it may just be enough to cut the 3mm all around the edges. Unless you really like the looks this also does not have to be super precise, the gasket will cover slight irregularities. here we use a black marker and "erase" it with a dremel to know when to stop and not overshoot. also you have access to super fuel, which will be enough in itself. in india fuel is shit and 92 RON is the height of "high octane" and even that is only available in few stations.

You can try putting it together and run it without changing the head, if problems arise then do the cutting. you can re-use the gasket, we do it here all the time (if not you can get an extra set in the shop).
Remember to re-fasten the head bolts after 500km, forgetting this has lead to leaking head gaskets.
 
Great - thanks... I'm going to order a 0.5 mm thick 3d-printed aluminium gasket and see if it fits... it's only gonna cost €20 or so. If it doesn't fit or it feels too tight, I'll hit it with the dremel
 
This may have been asked elsewhere but I havent yet run across the answer. Best case scenario., ideal big bore upgrade, what parts (on top of the complete kit, of course) and mods are recommended? Not the plug and play route but ideal scenario, for best results, orgasm on demand, big bore ugrade. I will easily end up with more money in this bike than I paid for it so I am going all in. I don't mean farkle the crap out of it with unnecessary bling. I am talking maximum rideability without losing the magic that is the 411 (477). I live close to Cogent Dynamics (high end suspension guy) so I intend to take my himi to him after I sort out the rest of the bike. Sorry for the ramble, I wanted to add context to my query.
 
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Larger throttle body, if possible, and a reprogrammable ECU.
Have you installed a Cam?
 
Hey folks,

So I've been thinking about this and the use of additional gaskets made me think - if you cnc'd an aluminium section using the gasket as a template,...

Thoughts?
If you use copper you can do this with hand tools.

I did this way back when I built a mongrel bike. I built an engine out of parts. It had a 500 barrle but a 350 head which raised the compression ratio too much. I had no spare money so it was a case of making it work as cheaply as possible.

Took a sheet of copper about 1/16", held it aagaist the base of the cylinder and gently tapped it with a ball peen hammer. That created the mark needed to cut out the cylinder bore part of the gasket.
After cutting it out, I placed the copper on the cylinder and tapped around the edges to get the exterior shape.
Then followed by the holes needed for the cylinder bolts, for which I used a suitable sized ball bearing. It sounds crude but the result was neat and worked.
I didn't have to worry about cam chains though, the engine had pushrods and there was enough adjustment available in them to compensate for the extra length.
 
I didn't have to worry about cam chains though,
Yeah, I did one from copper too back in the day. But in this case the chain is the issue. so copper likely wont work or any material of thickness more than a paper strip. You can use 2 base gaskets but the stock gaskets are very thin and made from paper.
 
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