Honda Spree and Elite 50 Forums

Compression for my '85 Aero NB50M AF05E is in the 90psi neighborhood and after taking it to a local Honda motorsports repair shop they identified some scoring on the cylinder walls telling me that they need to bore and upgrade the piston to 41.25 or 41.55mm. I've looked around at aftermarket top end replacements as well as larger pistons.

So it looks like:

$40 for the piston + $70 for bore job = $110 (or) $85 for the top end kit (or) maybe a Polini or Malossi BBK which I'm not sure I want to go for since I'm really looking for longevity over performance. I also don't really want to spend too much money on the necessary oil and fuel upgrades that are needed with that.

Can anyone shed some light on the quality of this top end kit or should I stick with the bore+Honda piston? Could someone also confirm that this piston will be the correct 41.25mm for my AF05E? I just got that info from Wikispreedia. Thanks!

Greetings:

Talk to RedEftperformance about the Malossi 65 cc running stock everything else. Longevity won't be compromised. Way better performance for little more cost.

you might do the whole top end over to find the crank seals or somthing else leaking to do with the crank case. Then again if it is the crank seals once they are replaced it one less thing to worry about. this is the best time to go BBK for sure, why not.