Curiosity BGM177 or VMC177 on a Reed Valve Stella
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Addicted
2007 Stella 150
Joined: 02 Nov 2019
Posts: 664
Location: Rochester, Minnesota
Fri May 08, 2020 4:42 am quote
Just sitting here thinking and looking at a few choices if my PM Tuning Exhaust doesn't help get me to 60 MPH. This is fairly flat ground, no real hills i'm talking about. Thinking more of a plug and play at the moment. I could work on the transfer ports a bit if needed, thinking stuff a plug into the hole around the crankshaft hole, grind away and clean up when I'm done. I think this may be buried in another on eof my threads but even I'm having issues finding it this morning, and thought a dedicated thread might be nice.

I like the idea of the BGM 177 because of it flexibility with setting squish heights with the drop into the cylinder head. I think a few here have looked at port timing with the BGM not sure how they look with a 57mm crankshaft. I have seen and need to find the BGM numbers in their cylinder literature.

I have also been told a VMC 177 works well, with the Stella motor. Again no idea what to expect for port timing numbers with a stock 57MM crank.

For those of you that have gone from a DR 177 to one of these kits have any real world input?
Molto Verboso
One or two fun scoots....nothing too precious
Joined: 17 Jul 2013
Posts: 1457
Location: UK (South East)
Fri May 08, 2020 5:34 am quote
The BGM will give you great power, relatively low down, but on a 57, you'll run out of RPM fairly quickly. Mine probably never hit much more than 6500 in 4th, although it was upgeared to 23/68 in a PX150 with 100/90 tyres, so that translated to an easy 65+ mph. For real power and revs, you'll want a 60mm crank with either kit. I have a VMC177 in a. box, and it's timings with a 57 are very low. See my thread about my aborted lockdown challenge.

[Edit] I used a DR177 prior to the BGM.
Addicted
2007 Stella 150
Joined: 02 Nov 2019
Posts: 664
Location: Rochester, Minnesota
Ossessionato
05 Stella, '62 VBB, 76 Sprint V, 63 GL
Joined: 16 Jun 2011
Posts: 2567
Location: Chicago. Well, Evanston, but that's almost Chicago
Sat May 09, 2020 4:16 am quote
You'll be reed-limited pretty quickly if you're on the stock stella reed block.

I run a BGM 177 on my Stella motor and get loads of power, but it's a beast of a build, so I'm not sure mine counts.

I can't comment on the VMC, but I might be interested in checking it out just for giggles at some point.
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