HW77 Tuning

[dtdukok]

I’m going to try the ‘boil it like a bunny’ method just out of absolute curiosity 😆

[bozzer]

Ps, what’s the difference to look at between 25mm and 26mm seals?

Thanks,

Darren

1mm

You just couldn't make it up.



I'll bet my house you have a 25mm. It's quite common to fit new piston seals and the power be as low as 9fp due to a tight seal. It won't take much to tweak it down and get the power up.

It'll be interesting to see if the boiling works. I've never done one that way. Always done mine with some very fine wet n dry spinning in the drill. Works and is really quick. Well ... do it a bit at a time.

Good luck

[dtdukok]

‘The difference to look at’ not ‘the difference in size’.

As in ‘is there I difference in profile or something else at first glance - without measuring them.

Muppets 😆

[bozzer]

I know ... but it was funny. Well ... tickled me.

Yours will be 25mm. A set of verniers will prove it. A 26mm seal in a 25mm tube is going to be silly tight and I can't see you getting 11fp with that set up.

Get her opened up and get that seal resized. Let us know how it goes.

[dtdukok]

It is 25mm and I have a pan of piston soup bubbling away on the stove now 👍

I’ll let it cool, clean it up and let you know.

Thanks,

Darren

[archie]

Surely if you try to resize the head in a drill the pressure of the abrasive paper will just stop the head turning whilst the piston turns ?

[bozzer]

Archie

Gently pressure and it works fine. The seal will continue to spin with the piston. If you try and grab it hard then yes the seal will spin on the piston head. Gentle ... and it's fine.

[deejayuu]

Surely if you try to resize the head in a drill the pressure of the abrasive paper will just stop the head turning whilst the piston turns ?

String wound tight betweeen the piston head and seal will lock it in place. Just don't forget to remove it after