Unboxing a CMR 47mm AF05 BBK

[mr pibbs]

Just got her in the mail today.







Not sure what to think of this: What should i do, if anything? Do i need to smooth that out with a dremel?

[bradthreee]

I would send the thing back Mr. Pibbs. It looks to be a manufacturing defect.

Save a few extra bones then get the Polini or Malossi instead.

[tw39515]

second that glad i ordered the polini

[elitedio]

Yes you should smooth that nub off and chamfer all the ports so that you don't snag a ring. Good setup is critical no matter what brand.

[Wheelman-111]

Greetings:

My limited experience with the Italian brands (2 bores) suggests they're too proud to ship anthing in that condition.

That said, with due care and attention it can be adjusted as suggested and installed. The bad rep of the Asian kits probably comes from end users failing to perform this final inspection. The added cost of the Italian kits is attributable to having craftsmen do it for you.

My Nikasil kit was probably Taiwanese too, but I found only the ports upon which to improve.

[Bear45-70]

I would say from looking at the shape the parts you recieved are in, that whoever the * "KECNI" (if that is what the letters actually are) is need to improve his printing and his method of quality control inspection.

That said a dremel tool can fix all the issues, but you shouldn't have to "FIX" a NIB (New In Box) product.

[mr pibbs]

Smoothing out edges and corners of holes in the side of the bore look obvious to me, but how do i polish the bore such that it is really smooth and ready for a piston after i dremel off the little nubs?

[evilone]

Hey Bear, looks like maybe it's "Keoni" from VTCycles . Maybe inspected means to see if all parts are there and where you go from there is up to the purchaser?

[Clivester]

Looks like a Char-Mo cylinder from VT cycles. Those ports certainly look like they need cleaning up! Id just do smoothing and edge chamfering. Trying to increase port size is dangerous unless you know what you are doing or want to experiment! Just smooth off the burrs and casting sand irregularities.

This may help to see what the port finishes should look like (though its not a Honda 50cc!).

http://www.apriliaforum.com/forums/show ... p?t=177390

The cast internals look too rough to me and the port edges too sharp. Cylinder looks like it was honed ready for the piston. The skirt is on the thin side, likely a combination of less precise casting and the overboring required to up the cc's, but noot much you can do about that.

[novs86]

I would say from looking at the shape the parts you recieved are in, that whoever the * "KECNI" (if that is what the letters actually are) is need to improve his printing and his method of quality control inspection.

That said a dremel tool can fix all the issues, but you shouldn't have to "FIX" a NIB (New In Box) product.

I agree with Bear, You shouldn't have to fix a NIB product! Send it back.

[noiseguy]

You didn't say who you got it from.

I'd contact the seller and let them know the condition of the kit. The stuff at the bottom of the bore isn't a big deal; that will clean up. I'd be a little more concerned about the transfer port, which looked either cracked or just a poor casting. Let the seller advise you on whether they'll send a replacement or if this is typical for these kits. Then you'll need to decide what to do.

These less expensive kits will require cleaning up and dressing the port edges (which look razor-sharp on that bore), if you expect to get any miles out of it. That's the cost saving... more work for you.

[bakaracer]

Those are typical for the taiwan kits.use a dremel and use diamond bits to clean off the nub and to clean up the port.

[mr pibbs]

Those are typical for the taiwan kits.use a dremel and use diamond bits to clean off the nub and to clean up the port.

yeah, it wasn't in that bad of shape. I smoothed it out the best i new how and threw her on there!

It was not my intent for this to become a bash CMR thread, there was just so little information out there on them I wanted to share my experiences.

For all the polini fanboys (please don't take offense), for me this is a hobby. While i do want reliability and the like, I am not racing and I am not necessarily looking for as much power as can possibly be had. When it explodes, we will all have learned something. When it works well and scoots fine for a few thousand miles, we will also learn from that. I just wanted an inexpensive upgrade of displacement. Gears are on route.

If you are interested in the performance of the CMR I will try and chronicle my journey on the Mad Max scooter build thread.

Happy scooting

[maddog]

47mm kit with a stock crank= you will learn the hard way on how not to build an engine...

[mookie]

why you wanna hate on us stock crank(new) 47mm guys?