450cc Upgrade

Sold out – wait for the 477cc to hit the road!


I am always amazed to see how people try to squeeze a bit more power out of the Himalayan by purchasing often expensive equipment like an open exhaust, a Powertronic, air filter, spark plug, and whatnot when the solution to solid torque increase is clearly an upgrade of the displacement. Always was, always will be. If you ONLY do that and forget about all the others you WILL have a tangible increase in torque on ANY Himalayan as has been experienced by all our test riders, customers and myself.

Our 450cc piston has proven itself in literally thousands of km driven on EFI and carburated Himalayans alike. In India it was tested on a long range trip to the Himalayan mountains and in Europe from south Italy all the way to the tip of Spain and back with long parts of high speed riding on EU highways.
It is by no means an untested piece of technology. It is used in otherwise unmodified bikes, carb and EFI, and in combination with the Powertronic and also our own very simple fuel flow control device.

You can now order the 450cc piston/head gasket set consisting of:

  • Piston complete with rings and pin
  • Modified head gasket to fit the bigger piston

Price is 198.- € plus 7.-€  shipping inside Europe,
28.-€  intl. shipping (rest of the world).

If you have a carburetor bike you need not change anything, the UCD33 carb is good for this upgrade without any configuration changes or re-jetting.

We have run it in EFI bikes without re-mapping and it works, however feel free to use a Powertronic or similar device.
Alternatively you can use a small potentiometer to control the EFI temperature sensor output which costs pennies but requires some knowledge to calibrate, or buy it from us for 60.- € . It gets spliced into the cable between the temp sensor and the EFI, a 1 minute affair. No programming, just a little tuning while you ride to find the optimal position for your elevation.

For this engine upgrade we only supply a piston with gasket, rings and pin but no cylinder as shipping heavy stuff is still slow and expensive and you could just as well have your own cylinder bored locally for a few bucks, as low as US$45.  You can then upgrade your engine for under US$300.-  all told.

Fuel flow regulator device
Fuel flow regulator device
The cylinder wall after boring remains thick and stable:
The cylinder wall after boring remains thick and stable:

Frequently asked questions

How to do the upgrade – shown on Youtube:



Questions, ideas, any kind of input? Please contact us.

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Would you be interested in our 450cc package? Live

  • Yes, very much so
    61% 92 / 149
  • Possibly, not sure
    12% 18 / 149
  • Maybe after my warranty is expired
    16% 25 / 149
  • Probably not
    2% 3 / 149
  • Absolutely not, happy with what I've got
    7% 11 / 149