125-200cc I made my own 165 Kit

Hi there,

i was looking for a used WB 165 kit for a while but had no luck.
When i asked wallybean for a new one figured out it will be very expensive to get it to germany as the exchange rate wasnt on my side... :-(

I still wanted one but had to get around the money problem first.
So i asked wally a few questions, ordered a piston and thats how it all started...


I m very curious how it performs when i put it on my bike- cant wait to be fit to ride it again.


Note- this kit is based on all the experiences with the WB Kit- i did get a lot of help from wallybean- without him i dont think i would be that far- thank you very much for your help wally!

But i was working with some local companys to see if this work could be carried out here for a similar price.

Ohh looks promising!

So how did you do it? just curious.... I would love to find a 2 ring piston.....

this is a 2013 WR cylinder i was using, but when i realised i had to do some welding my welder did blew up (and thats when the project became even more expensive than a wallybean kit)...





from now on i did using a old style cylinder which was an easier to start without welding work.

I picked it up today from beeing overbored and replated






I did made the powervalves fit, put new seals and the pv back in place- i m waiting for the cylinder head now.

i m using the single ring yz style piston, havent made my mind up using another piston instead as these wössners are very durable.

Looks good.... which YZ piston are you using? or what year?

05 onwards like always- i run this YZ so i have 1 piston for both bikes ;-) - i also use them in my stock WR/CR cylinders because the have 2 holes bored into the exhaust side- but you have to get the head modded or use an extra thick base gasket to make sure its not detonating.

What bore size? Standard? over?

The stock piston is for a 54mm bore,
144 is 58mm bore
165 is 62mm bore

As you see it isn't that easy to do on the newer cylinders. You have to weld up both the rear transfer slot and the bore holes for the power valves. It would be pretty hard to fix your 13 cylinder at this point. Then you also have to re-port both the rear transfer and the exhaust port accordingly. Now figure in your time to do a good job re-machining your power valves and get the height right and the bottom clean. Port and polish the exhaust port and knife edge your transfers too. Machine the head correctly and there you have it. Of course you need to get the piston kit supplied. When you get it all figured out you will find that there isn't much room for "profit". If you don't like doing it as your hobby you will give it up quickly as your $/hr are pretty miniscule.

The older cylinders are easier from the stand point that you don't need to do any welding. They are harder to fit the power valves and the rear transfer is tougher to re-port accordingly because of its small size. Don't make any mistakes on the power valves as they are hard to come by. None of this is impossible from a do it yourself point of view but you will quickly learn that getting everything "right" takes time and experience. Also when you start sourcing piston's figure that cost in if you aren't going to buy at least 25 at a time. I think if you buy only 10 from Wossner the price will be ~$170 each.

Also just as an aside it is much better to pre-port that rear transfer before you bore. You are going to have a hard time porting it that far now without flaking the lining. I actually do 90% of the porting work pre-boring.

Just as a side note. I have been doing this for quite a few years and have yet to show a year end profit from my little business. I don't cheat on the taxes and only write off my actual bike related expenses. So it pays for most of my hobby but not all. Average income for a year was ~$40,000-$50,000 and have averaged a $5000 loss each year. 2015 was my worst year as income was half and while most costs were accordingly less my bike expenses stayed the same so my loss this year is double: hobby didn't pay for much of my fun this year(2nd year Italian Husky out of production). The question my tax person asks me each year is why do I do this for this result. That is why it needs to be a hobby. If you are doing it all correctly your $/hr is between $10-$20. Of course that doesn't count the times you eat the cost of rebuilds/top ends because of problems that may or may not be your fault.

this industry never had paid very well... lol

Well done miezie666. I hope you enjoy your 165 as much as I do.
Reading this thread just made me appreciate even more the effort and attitude required from Walt to make the 165 a reality. I tips me lid to ya.

Hey all,

I am not complaining at all. I love what I do, I just want to make sure that anyone wanting to do this type of thing goes into it with their eyes open and a healthy sense of reality for what the final numbers will look like. I have built hundreds of kits and learned a great deal along the way. Always stand behind your work and give the benefit of the doubt to the rider/owner. No one loves their big bore Italian Husky more than I do. If it had a button, I would never buy another bike.

This year is stacking up to be about the end of the kit as a regular hobby as demand has dropped off by at least 50% for the second year running. Not an issue, just reality. I will always offer parts and service. Working on being able to offer something for the new Husky small bores but it is not nearly as simple. I really like a lot about the new Husky small bores. The room for expansion on that platform is limited though. Its a work in progress.

I hope Miezie gets his 165 ripping. Such a great motor.

Its like wally said- its not that easy as it seems to be. I had to pick up the cylinder from the machine shop to make sure the porting will be correct, rework it, dropping it off at the shop again... the time and effort just to get things done- unbelievable. But hopefully in a few days i can start the engine.

A last interruption, I applaud Miezie for doing this on his own and will always help when I can. I will continue to build kits it is just at the level where it doesn't really fill enough time to be called anything more than a mini-micro hobby.

Hopefully GG or swm continue the motor maybe with estart Walt!

We can always dream.

Yeah be a shame to see such a solid donk with much potential go the way of the dinosaurs. For what it's worth your kit rocks mate!