80cc Cylinder G4

Lukesky36

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Joined
Oct 3, 2018
Messages
420
Found it on Ebay So can anyone explain what the idea behind cutting the transfer ports out?
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Jag

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Oct 6, 2018
Messages
172
It was an older style, I think. I had a bike berry cylinder like that. It wears down rings faster, and allows for better flow.
 

Spare_Parts

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Nov 29, 2017
Messages
1,588
That is the Flying Horse cylinder. It is supposed to allow more flow. The part in the middle of the transfer is to help with ring wear. Never used one yet.
 

Sumsloppymeet

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Joined
Aug 7, 2017
Messages
565
ive actuaally got one of those right now ported it some widened the split exhaust some matched it with the crankcase i polished like a mirror almost ill probably have it back together in a day or so i was curious bout the same thing hes offering steel bore ones now too if im reading right
https://www.ebay.com/itm/BLACK-Upgraded-80cc-8mm-wider-intake-port-40mm-cylinder-STEEL-BORE-G5/143030409160?_trkparms=aid=111001&algo=REC.SEED&ao=1&asc=20160908131621&meid=72fd948f9a9947808e3a516c8a7b9f37&pid=100678&rk=6&rkt=15&mehot=es&sd=222841509473&itm=143030409160&_trksid=p2481888.c100678.m3607&_trkparms=pageci:77514b75-0a18-11e9-bc66-74dbd1803d0a|parentrq:f16b00991670aa11adc4d6b3fff416a4|iid:1
 

JerboaJohn

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Joined
Jul 29, 2018
Messages
1,234
what gets me is the always open transfers. I'm just trying to learn about port timing, and this throws a monkey wrench into the works. really clean casting tho mine's not scruffy at all! the split exhaust seems small and needs widened. I'll probably leave the transfers alone. so much simpler. oh and it came on 6mm studs but fits 8. other than the intake being square and small exhaust, I bet it outflows a lot of stock jugs. once the transfers r open, they open more n more until max at BDC. o_O
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I got mine from BGF on a complete motor he lists as 2019. I'll start a thread on it bcs there's some weird stuff abt this engine lol
 

JerboaJohn

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Jul 29, 2018
Messages
1,234
not open so much I see now at BDC jug back on. better widen them :) and the piston does not reveal the ex port all the way.
tports_g4.jpg
 

Spare_Parts

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Joined
Nov 29, 2017
Messages
1,588
what gets me is the always open transfers. I'm just trying to learn about port timing, and this throws a monkey wrench into the works. really clean casting tho mine's not scruffy at all! the split exhaust seems small and needs widened. I'll probably leave the transfers alone. so much simpler. oh and it came on 6mm studs but fits 8. other than the intake being square and small exhaust, I bet it outflows a lot of stock jugs. once the transfers r open, they open more n more until max at BDC. o_O
View attachment 87218View attachment 87219
I got mine from BGF on a complete motor he lists as 2019. I'll start a thread on it bcs there's some weird stuff abt this engine lol
It's the same bottom end as the super rat- GT5 SR. Can't wait to see pictures! I have been eyeballing that bottom end lol, sounds funny!
 
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