05-15-2017, 12:52 PM
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#1 |
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Join Date: Apr 2016
Posts: 49
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Hawk Beef UP?
so Im sitting here waiting on my 2017 to land stateside and be delivered to me. As I impatiently wait for it to arrive, I read all the tech articles here and begin planning my wrenching. However, I do not see anyone posting about doing big bore kits on a hawk... they are available... I understand the risks, I get it... so why doesnt someone give it a try? I see a bigbore kit on ebay for these bikes for about 70 bucks... ( 63.5mm piston) anyway, just curious... it would be interesting...
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05-15-2017, 01:52 PM
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#2 |
Join Date: May 2016
Posts: 237
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i think the hawk is has a 167 model engine.
63 would be a downgrade. its allready a big bore cg125 engine, not sure how much more it would take.. raise the compression by decking the head a bit maybey. |
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05-15-2017, 02:10 PM
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#3 |
Join Date: Apr 2017
Location: Omaha, NE
Posts: 7,953
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^What he said. this engine already has a 67mm bore, so putting in a 63.5mm piston would actually make it smaller. There used to be a couple of 70mm bore kits out there for these motors, but I haven't seen them around as much lately, although I am sure they are still out there somewhere. Going with a 70mm bore would give you a true 250cc.
Honestly, if you want to go for bang for the buck, porting the head alone would be a huge improvement. Nothing super aggressive, just a nice smoothing of transitions and a little cleanup. The best part about this is that it could be done for cheap. if you trust yourself to do head work at least. Otherwise, you will end up spending a couple hundred bucks to have a shop do it. As far as decking the head, you could do this as well, but being an aircooled engine with a kick starter and no compression release, I wouldn't get too silly. somewhere around .5mm to .8mm would be about as far as I would go personally.
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2018 Hawk 250 - Full Mod list here. http://www.chinariders.net/showpost....62&postcount=1 Hawk Information and Resource guide: http://www.chinariders.net/showthread.php?t=20331 2010 VFR1200F - http://chinariders.net/showthread.php?t=20708 |
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05-15-2017, 03:35 PM
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#4 |
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Join Date: Apr 2016
Posts: 49
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I was just curious.... i dunno why i thought 63.5 mm was larger piston.... I havent pulled one apart and done research.... just looking at options that are available. ( internet research) and experience ( boring and stroking a 68327 sbc to 355ci yields some impressive results....) but i digress just seeing what was out there and musing on possibilities...
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05-15-2017, 04:21 PM
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#5 |
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Join Date: Apr 2017
Location: Omaha, NE
Posts: 7,953
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Trust me, I understand. I am a hot rodder at heart. With these motors, you csn still poke and prod some power out of them. I can't imagine more than about 20hp out of one of these without hurting its reliability or sacrificing the ability to run regular gas or its nice grunty bottom end power.
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2018 Hawk 250 - Full Mod list here. http://www.chinariders.net/showpost....62&postcount=1 Hawk Information and Resource guide: http://www.chinariders.net/showthread.php?t=20331 2010 VFR1200F - http://chinariders.net/showthread.php?t=20708 |
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05-16-2017, 12:32 PM
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#6 |
Join Date: Mar 2009
Location: Sardis, BC, Canada
Posts: 25,977
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Given the frame of architecture, 229cc is just about as far as you want to push the envelope. You can get close to 270cc, but that is a liquid cooled motor that is commonly used for three wheeled trucks. I prefer to just enjoy this air cooled engine for what it is and focus on optimizing everything else.
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Weldangrind "I figure I'm well-prepared for coping with a bike that comes from the factory with unresolved issues and that rewards the self-reliant owner." - Buccaneer |
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05-16-2017, 05:15 PM
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#7 |
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Join Date: Apr 2016
Posts: 49
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i know... i do... but... im a tinkerer at heart... i like to PLAY with things...try to get more POWAH!!
seriously though... just asking around... maybe ill buy a complete bike with a blown motor and rebuild it as beefy as i can... see what it can do..even if it shortens the life... low investment build... well see.   
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05-16-2017, 05:22 PM
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#8 | |
Join Date: Mar 2010
Location: Volcano, Ca
Posts: 7,071
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Quote:
Didn't he curl that swing arm up like a banana?
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"Light a fire for a man, and you heat him for a day. Light a man on fire, and you heat him for the rest of his life." 2007 Suzuki DRZ400S (SM convert) 2009 Q Link XP 200 1967 BSA B25 250cc Starfire 2022 Royal Enfield Interceptor 650 2023 Royal Enfield Scram 411 1948 Royal Enfield Model G 350 |
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05-16-2017, 10:03 PM
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#9 |
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Join Date: Apr 2017
Location: Omaha, NE
Posts: 7,953
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While I wouldn't go so far as to put a 450 in one of these, a mildly hopped up 167fmm is most likely not going to go folding the bike up.
__________________
2018 Hawk 250 - Full Mod list here. http://www.chinariders.net/showpost....62&postcount=1 Hawk Information and Resource guide: http://www.chinariders.net/showthread.php?t=20331 2010 VFR1200F - http://chinariders.net/showthread.php?t=20708 Last edited by Megadan; 05-17-2017 at 12:29 AM. |
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05-17-2017, 03:43 AM
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#11 | |
Join Date: May 2016
Location: Bismarck, ND
Posts: 868
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Quote:
His pictures come up on the home page all the time.
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2015 and 3/4 RPS Hawk 250. Most people would call it a 2016 but the MCO didn't. |
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05-17-2017, 11:22 AM
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#12 |
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Join Date: Mar 2010
Location: Volcano, Ca
Posts: 7,071
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He was a fun member and I think showed up last month temporarily. WA was always up to something mechanical. I'm sure he's probably engineered a Mars lander out of what he has in his garage by now.
__________________
"Light a fire for a man, and you heat him for a day. Light a man on fire, and you heat him for the rest of his life." 2007 Suzuki DRZ400S (SM convert) 2009 Q Link XP 200 1967 BSA B25 250cc Starfire 2022 Royal Enfield Interceptor 650 2023 Royal Enfield Scram 411 1948 Royal Enfield Model G 350 |
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05-17-2017, 11:56 AM
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#13 |
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Join Date: Mar 2009
Location: Sardis, BC, Canada
Posts: 25,977
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He's still active on his dune buggy thread.
__________________
Weldangrind "I figure I'm well-prepared for coping with a bike that comes from the factory with unresolved issues and that rewards the self-reliant owner." - Buccaneer |
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05-18-2017, 09:43 AM
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#14 | |
Join Date: Dec 2016
Location: Western PA
Posts: 363
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08-22-2017, 01:41 PM
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#15 | |
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Join Date: May 2016
Posts: 237
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Quote:
that said, I found this on cleveland cycle works website.. Thing is they dont mention the bore size.. just big bore https://clevelandspeedshop.com/colle...ton-gasket-kit Maybey its for a different cg engine.. How big is big? I found the stats on the add for the piston alone.. Bore 69.5mm - Stroke 65mm So this is a smaller bore then the cg250 223cc, must be for one of their smaller bikes. |
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