1981 125 water cooled HIRO engine.

[mbha]

Hi,
I have an Aprilia 125 1981 that I am about to restore. It seems to be the same piston as KTM?
I would like some information on the engine, bearings and such.

I am also looking for the housing of the reed valves. The one bolted to the cylinder. Unfortunately mine is missing so I am trying to locate one.

[mbha]

Maybe someone has a manual scan?

Found it!!!
http://mototgmvintage.altervista.org/bl ... 980-82.pdf

[THIERRY]

Nice bike!

On the left side of our HOMEPAGE, you can find everything about HIRO and APRILIA, and it's free.. Just click on it!

[mbha]

Hi,
Yes. Lots of great information but a little hard to find since I don't understand French sadly.
Does anyone know if there are sidepanels and seat covers available anywhere?

I also have an issue with the reed valve configuration. I'm missing the entire reed block/house, cage, valves and intake manifold. But I'd like to make a new block with a normal style reed valve instead of the open piston port intake in the middle and reeds to the sides which goes directly to the crank-case and transfer ports. That way I hope to use a KTM 54 mm 125 cc piston with a hole on the intake side for the boost ports.



France MXdN winners in 2014 and 2015 (for sure)

[birdy459]

the piston is a fair price for the valves, YZ 125 1981-82 with the pipe and it takes Hollow out the aluminum to place the box has clapte yz, and make a decoupe the piston the same as on a yz cost admission not Ktm

[mbha]

Thank you birdy 459

Let's see if I understand right?

1. I cannot use the KTM piston, but I can but these HIRO piston from ebay?

2. I can use the intake and reed from YZ 125 1981-82 if I remove some material from marked
red?

Do the yz 125 reeds fit bolt on, onto the cylinder?

[birdy459]

Thank you Birdy 459

Let's see if I understand correctly?

1. I can not use the KTM piston, but I can not but HIRO piston on ebay?
Yes the piston is flat on KTM, slightly tapered on hiro
2. I can use the contribution and Reed YZ 125 1981-1982 if I remove certain materials from marked
red? yes, the pipe can be fitted without admision big change with the systhéme YES
Have vis the YZ 125 reeds adjustment on the cylinder?
yes bit for the valves is within the inlet conduit

[mbha]

What do you think of this Husqvarna reed setup?

[THIERRY]

I don't really understand , why don't you use HIRO OEM parts to rebuild the engine?

[mbha]

The Husqvarna reed block is perfect. I will post updates.

[mbha]

I don't believe I can find all missing parts for the original overly complicated setup. I need the block house and the rubber insert between the reed halves.

[THIERRY]

We can find it new, OEM parts .

[mbha]

[mbha]

[mbha]

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