The 50

[TALLIS]

Since the 50 is going so well, and is basically being used as the town bike, I thought I should be prepared.
Where are you boys getting your rg50 pistons?

[F5 Dave]

Um. . . Phil Turnbulls?

[Bert]

Since the 50 is going so well, and is basically being used as the town bike, I thought I should be prepared.
Where are you boys getting your rg50 pistons?

RMX50 piston

[TZ350]

Where are you boys getting your rg50 pistons?

Off Ebay



The Wiseco Suzuki JR50 and Kawasaki KDX50 piston is a direct replacement for the old RG50 piston.

[richban]

So now have all the bits I need to do the first build on the AM6. Seat of pants build that is.


The plan! Use the new mega race 30hp ali cylinder (stage 6 sport cylinder really) I brought from Europe.


It actually looks ok. Honda sort of layout.


But the exhaust duct looks really small at first glance compared to standard. The cylinder will need to be raised about .9 of a mm to get the transfers opening around 84 deg atdc.

First thing I will do is port the cases there seams to be loads of big sharp edges around the place. I will post some pics when I get stuck in over the weekend.

[TALLIS]

Off Ebay



The Wiseco Suzuki JR50 and Kawasaki KDX50 piston is a direct replacement for the old RG50 piston.

Thanks Rob, great.

[TALLIS]

The plan! Use the new mega race 30hp ali cylinder (stage 6 sport cylinder really) I brought from Europe.

I hope the box dosnt say race on it, not in English anyway. looks nice tho!

[richban]

I hope the box dosnt say race on it, not in English anyway. looks nice tho!

Ha ha. No the word race was not on the box. Well it took me 2 hours to clean up the port windows. The nikasil was pushed over the ports quite a bit. The exhaust port exit is way small compared to standard. Also the transfer and boost port ducts are different from the cases. I think this cylinder is for a later model Derbi. But is says it fits the AM6. That is ture, it dose fit but not so good. I think after I match it all up there will be quite a bit of case volume. Maybe. I will cc the cases when its all back together and see where I am.

[F5 Dave]

Piston looks good except pin is pretty low.

Strange duct but would suit a transition insert yeah?

[sonic_v]

So now have all the bits I need to do the first build on the AM6. Seat of pants build that is.


The plan! Use the new mega race 30hp ali cylinder (stage 6 sport cylinder really) I brought from Europe.


It actually looks ok. Honda sort of layout.


But the exhaust duct looks really small at first glance compared to standard. The cylinder will need to be raised about .9 of a mm to get the transfers opening around 84 deg atdc.

First thing I will do is port the cases there seams to be loads of big sharp edges around the place. I will post some pics when I get stuck in over the weekend.

Does the exhaust flange have a diameter of 28 mm? This is what the standard cylinder is.

[richban]

Does the exhaust flange have a diameter of 28 mm? This is what the standard cylinder is.

Yep 28mm. The exhaust duct exit is way smaller than standard though. On the standard cylinder it transitions form the port oval to around 24mm cross section area on exit. The new one is way smaller. It should give me lots of scope to adjust it. So a good thing I think.

[richban]

So I have split the engine. I must say it's a rather heavy duty little thing. Quite impressed how well made it all seams.

I have started porting / matching the cases to the barrel. It all looks quite straight forward. The barrel has no dowels to help line things up. I need to sort that so I can be as accurate as possible when grinding away.

As you can see there is a bit of dead space that needs filling between the barrel and cases. On the inlet side I plan to blend this into a nice big fat radius. I will also radius the duct entry on the barrel. Looks like I will end up with more case volume than it had as standard. I will cc it when I am happy with all the case work.







I did have a mad idea that it needs a dry clutch. We will see.

[cotswold]

a big thanks to those involved with helping me get this former beach toy which would have had 1/2 the manufacturers claimed HP when I first got hold of it up to a respectable nearly 14.
the latest to become involved would be Kel, he drew up my new head inserts and Kerry who made them for me, you boys rock
Thanks boys

even upside down (wtf) they look sweet

[seymour14]

Be good to see it in action at the GP. The F5 should put up a fantastic amount of riders this year me thinks!

No worries.

[richban]

a big thanks to those involved with helping me get this former beach toy which would have had 1/2 the manufacturers claimed HP when I first got hold of it up to a respectable nearly 14.
the latest to become involved would be Kel, he drew up my new head inserts and Kerry who made them for me, you boys rock
Thanks boys

even upside down (wtf) they look sweet

Nice one. I will be there soon. I have just been in the shed with the grinder and diamond files putting a nice radius on the transfer ducts and boost port. What comp is that. I was thinking of going 15:1.