|
|
Post by rcq92130 on Aug 20, 2014 15:09:45 GMT -5
So my BMS Palazzo is a 150cc scooter. Or so I thought.
But a few days ago - in the thread titles, "150cc Gy6 died - how bad is it" the topic came around to possibly getting a new engine, and the ScooterDogs $550 "200cc GY6" came up as a 'great alternative'
Except that some here claimed this isn't really a 200cc engine - only 170cc or so. I couldn't buy that so i called ScootDwgs and asked.
Sure enough -0 this is NOT a 200cc engine; just 'called' that. It is, in fact, only a 170cc engine per the salesman I spoke with. Further, he claimed "this is just the way Chinese engines are called - none of them actually have the claimed displacement."
So that got me to thinking .... what is the REAL displacement of my (allegedly) 150cc GY6??? The ScootDwgs salesman didn't know.
Anyone here know what is real and what is Memorex?
|
|
Freshman Rider
Currently Offline
Posts: 86
Likes: 7
Joined: Mar 17, 2013 21:08:40 GMT -5
|
Post by korn858 on Aug 20, 2014 15:30:15 GMT -5
I don't know why Scrappy calls it a 200cc. The only difference that I can tell is that 150cc is really a 125cc thats been bored to a 150cc, which makes it a true 150cc. However, Scrappy's 200cc (170cc) is a 150cc engine that's been upgraded to a170cc. The good news is that Scrappy's engine can be made into a 232cc. But if you look at the prices to do it; It'll hurt the pocket a little. Hope that helps.
In short stock 150cc, is a 125cc platform
Scrappy's 200cc (170cc) is a 150cc platform
|
|
|
|
Post by rcq92130 on Aug 20, 2014 15:36:53 GMT -5
Ah ha.
So my "150cc" ...
It's a 125cc platform, bored out,.
But is it really one hundred fifty cc as it now stands?
|
|
Freshman Rider
Currently Offline
Posts: 86
Likes: 7
Joined: Mar 17, 2013 21:08:40 GMT -5
|
Post by korn858 on Aug 20, 2014 16:07:43 GMT -5
Yup, just bored from a 125cc.. But, more directly it's indeed 150cc. It's actually something like 150.6 or something like that.
|
|
|
|
Post by pmatulew on Aug 20, 2014 17:34:12 GMT -5
Cubic Centimeters of displacement. The volume of air the piston (or pistons) suck in with each stroke. 1000cc = 1 liter
This is pretty common practice with scooter and motorcycle manufacturers. They tend to round up whatever the actual number is to the next higher class. (50, 125, 150, 180, 200, 225, 250)
Vespa 250 is really 244cc
Vespa 300 is really only 278cc
(They just feel bigger because of multiple valve and fuel injection)
|
|
|
|
Post by rcq92130 on Aug 20, 2014 18:58:48 GMT -5
Yes, of course they round up.
but this started from ScrappyDogs offering of a 200cc GY6 ... which turns out to only be 170cc. That's not 'roundingh up' ... that's false advertising, pure and simple. I'm actually quite disappointed.
|
|
Freshman Rider
Currently Offline
Posts: 86
Likes: 7
Joined: Mar 17, 2013 21:08:40 GMT -5
|
Post by korn858 on Aug 20, 2014 19:21:29 GMT -5
He does say it's a "161QMK" engine, so technically that says what cc it is. The add doesn't say 200cc. But yea, I had the same issue as you regarding the misleading title.
I will say the engine runs great. Strong from start to top speed. And the cooler definitely works to keep the bike cool. I went from 50-55 with the old motor, stock. To being able to hit 65 even on small uphill grades. The engine pulls very well up hills.
|
|
|
|
Post by rcq92130 on Aug 20, 2014 19:46:26 GMT -5
So if I got a 163cc big bore kit (no case grinding needed, supposedly) I'd be able to see the kind of performance you are seeing? At $75 that's a of a lot less expensive for the same result ... cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&vxp=mtr&item=181494972777'cause I'm only getting the same pitiful top end you were getting (50 - 55mph most of the time), and find that kind of pathetic. |
|
|
|
Post by shalomdawg on Aug 20, 2014 19:49:04 GMT -5
howdy and just a reminder though that the jaeger200 kymco and hd200 sym are indeed smaller displacement but definitely more engine and technology than an updated 150. if i remember right the sym was 173 but had 4 valve head and fuel injection and water cooling so it was putting out more like 14 or 15 horsies where the 150 cc air cooled are putting out less than 10. my 350 is labeled 350 but is actually 330cc but puts out almost 33 horsies. if the 150cc was putting out the same per cc it would be putting out 15 horsies. anyway that has nothing to do with the price of tea in china
lotsa miles and smiles to ya
ken
|
|
|
|
Post by scooter on Aug 20, 2014 20:24:27 GMT -5
"this is just the way Chinese engines are called - none of them actually have the claimed displacement." HAHAHA in other words "we are lying but hey everybody's doing it!" To get your real cc's use PI*R^2*H)/1000, where PI is 3.14159265359 R is the radius of your bore and H is your Stroke so that's ((1/2 bore)*(1/2 bore)*(3.14159265359)*(Stroke))/1000 use all metric measurements. wikipedia says a standard gy6 is 57.4 mm bore × 57.8 mm stroke (2.26 in × 2.28 in) So that's 57.4 / 2 = 28.7 That's my Radius now I square it: 28.7 * 28.7 = 823.69 and that's R squared now times that by PI is 823.69 * 3.14159265359 = 2587.69845 and that PI*Rsquared or PI*R^2 times that by the stroke: 2587.69845 * 57.8 = 149568.97 that's cubic mm divide by 1000: 149568.97 / 1000 = 149.56897 cc so about 149-1/2cc If I get a BBK that's 61mm with the same stroke then it will have a displacement of 169cc if I also add the "+8.2" 66mm "stroker" crank, my stroke will be 66mm and my cc's will be 193cc. Your BMS Palazzo is listed on gokartsusa as a 149cc with a 52.4mm bore by 57.8mm stroke. Here is a handy calculator: www.mk5cortinaestate.co.uk/calculator2.phpAccording to this chart at scrappydog, the "57" in my 1P57QMJ motor means it's a 57mm bore. If that were a 53, then it would be 53mm, etc. The "J" means it's a 150cc.  |
|
|
|
Post by rcq92130 on Aug 20, 2014 21:06:09 GMT -5
So that indicates a displacement of 125cc, but gokartsusa says the displacement is 149cc.
I know the engine exists in a 125cc variant, but think mine is bored out to 150cc (approx) .. so something (bore?) must be wrong.
still, the question remains: if I get that BBK, with 163cc, will my performance be about the same as ScrapDgs "200 GY6, which is way less than 200cc in reality)?
|
|
|
|
Post by rcq92130 on Aug 20, 2014 21:19:24 GMT -5
Oh - yeah, mine is a 1576QMJ also.
So ............. with 163cc would I get about the performance of the ScpDg "200"?
|
|
Freshman Rider
Currently Offline
Posts: 86
Likes: 7
Joined: Mar 17, 2013 21:08:40 GMT -5
|
Post by korn858 on Aug 20, 2014 21:32:12 GMT -5
I would think so. I know the variator, and weights are different then my stock 150. For example, going down a grade I could hit 8200 rpm with the 150 going 65 mph. With Scrappy's I've never been over 6500 rpm. Going down a steep grade I can hit 70+ and the engine is purring; doesn't sound or feel like its being over worked.
|
|
|
|
Post by scooter on Aug 20, 2014 21:34:23 GMT -5
Oh - yeah, mine is a 1576QMJ also. So ............. with 163cc would I get about the performance of the ScpDg "200"? You said the ScpDg was 170 and this says 163, so that's 7cc's difference. We can go WAY out on a limb and say that since the engine lists as 150cc for 8.6 HP @ 7,000 RPM then that could be said to produce 8.6/150=0.0573 horses per cc, so 0.057 * 7cc's = 0.4013 or 4/10's horsepower difference. But that's a real WAG. (Actually, I used that number to calculate the 125 and 50 cc motors and it's not a bad ballpark figure for the stock motors. .0572 hp per cc (or 1HP for every 17.5cc's) is the average of the 3) Besides, if they mean 170 when they say 200, what do they mean when they say 170?  |
|
|
|
Post by rcq92130 on Aug 20, 2014 21:44:48 GMT -5
Do you know if your casting supports a larger variator than the stock GY6 casting? I just got a Dr. P variator and it's about as large as you can got w/o hitting the sides of the casting. Maybe your engine allows a larger variator.... ?
ps: I never, EVER, get above 7200 RPm on my 150 ..............
|
|
