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11-07-2018, 06:29 PM | #1 |
Join Date: Sep 2018
Posts: 173
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Can you take piston cylinder off without messing with cam timing?
I got parts from RPS to repair my dinged up piston and messed up valves and head, and am wondering if I can pull the piston cylinder without having to reset the cam etc..
I tried searching here and google for it being documented for either the Hawk or original CG 125 and came up with nothing.. I don't want to offset the cam, crank, and magneto and see that the cam adjuster is on the piston-head, but it looks like it's just in the cavity under the push-rod holes. Thanks |
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11-07-2018, 07:51 PM | #2 |
Join Date: Jun 2011
Posts: 1,335
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No. It usually turns just a bit while feeding the chain around the sprockets.
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11-07-2018, 07:57 PM | #3 |
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Join Date: Oct 2016
Location: Houma, La.
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The CG250 is a push ROD engine so yes you can remove the cylinder without messing up the timing. No timing chain on the CG250.
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2024 Linhai 300 ATV 4x4 2023 Lifan Lycan 250 Chopper 2023 Venom Evader 2022 Lifan KPX250 2020 Kawasaki Vulcan S (Sold) 2004 Honda ST 1300 2016 Black Hawk 250 (sold) Keihin PE30 carb,125 main,38 slow.Pod filter,ported & decked head 10:1 CR,Direct Ignition Coil,15/40Sprockets,NGK DPR8EIX-9,De-Cat,Dual Oil Cooler,Digital Cluster 2016 Cazador180 XL 2014 Coolster150 JerryHawk250.com My YouTube Channel Last edited by JerryHawk250; 11-08-2018 at 07:27 AM. |
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11-07-2018, 08:50 PM | #4 |
Join Date: Jun 2016
Location: Hell
Posts: 2,408
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CG yeah cause cam inside bottom cases
Maybe add in roller rockers while you are there Messing with cam timing can’t be an issue cause such a simple motor n line up the dots I assume |
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11-09-2018, 08:34 AM | #5 | |
Join Date: Jun 2011
Posts: 1,335
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Quote:
Forgot that that engine is a pushy rod type. |
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11-09-2018, 08:45 AM | #6 |
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Join Date: Oct 2016
Location: Houma, La.
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Perfect opportunity to throw in some roller rockers. https://www.aliexpress.com/item/Bran...9-7f354bbbe4f6
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2024 Linhai 300 ATV 4x4 2023 Lifan Lycan 250 Chopper 2023 Venom Evader 2022 Lifan KPX250 2020 Kawasaki Vulcan S (Sold) 2004 Honda ST 1300 2016 Black Hawk 250 (sold) Keihin PE30 carb,125 main,38 slow.Pod filter,ported & decked head 10:1 CR,Direct Ignition Coil,15/40Sprockets,NGK DPR8EIX-9,De-Cat,Dual Oil Cooler,Digital Cluster 2016 Cazador180 XL 2014 Coolster150 JerryHawk250.com My YouTube Channel |
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11-09-2018, 12:59 PM | #7 |
Join Date: Jul 2018
Location: NEPA
Posts: 273
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roller rocker
WOW I am seriously tempted to try those !
It's snowing here now so im running out of dust to knock off the Hawk.
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2018 Hawk P&P Decked .040 off the head. 17/43 D.I.D. 428, NGK Iridium plug, DeCat, Wrapped pipe, Custom S.S. Muffler core, Nibbi PE30 115/35, L.E.D. Lights, Digital Cluster, USB port, Cutting Bord skid plate, Oil cooler w/ custom CRF oil filter inline, 5Wt fork oil, Rear Shock, CNC Back Rack, 30mm FAT bars, Bark Busters, ProGrips, Adjustable levers, Shinko 700’s lots of Loctite! |
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11-09-2018, 01:16 PM | #8 |
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Join Date: Oct 2016
Location: Houma, La.
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Even though any performance gain will be very small if any at all. Less friction does equal more power. It's one of the mods that I would do only if I was already pulling the cylinder off. I wouldn't pull the cylinder just to install them.
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2024 Linhai 300 ATV 4x4 2023 Lifan Lycan 250 Chopper 2023 Venom Evader 2022 Lifan KPX250 2020 Kawasaki Vulcan S (Sold) 2004 Honda ST 1300 2016 Black Hawk 250 (sold) Keihin PE30 carb,125 main,38 slow.Pod filter,ported & decked head 10:1 CR,Direct Ignition Coil,15/40Sprockets,NGK DPR8EIX-9,De-Cat,Dual Oil Cooler,Digital Cluster 2016 Cazador180 XL 2014 Coolster150 JerryHawk250.com My YouTube Channel |
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11-10-2018, 09:43 PM | #9 | |
Join Date: Jun 2016
Location: Hell
Posts: 2,408
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Quote:
Is there a difference? careful with Chinese details huh - around half the time I get stuff they are wrong and I am left fixing the issue. |
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11-11-2018, 10:17 AM | #10 |
Join Date: Jun 2011
Posts: 1,335
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Most of these bikes aren't 250cc. They are between 200 and 230cc depending on engine model. Cam profile and max RPMs are the contributing factors to roller rockers having problems.
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11-09-2018, 02:15 PM | #11 |
Join Date: Apr 2017
Location: Omaha, NE
Posts: 8,100
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I would be more interested in those rockers if they offered an increased ratio. For the dollar I think that would be the best "bang for the buck" if it could be done.
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Hawk Information and Resource guide: http://www.chinariders.net/showthread.php?t=20331 2018 Hawk 250 - Full Mod list here. http://www.chinariders.net/showpost....62&postcount=1 2024 Royal Enfield Shotgun 650 https://chinariders.net/showthread.php?t=34124 |
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11-09-2018, 04:35 PM | #12 |
Join Date: Jan 2012
Location: ChCh , NZ
Posts: 2,265
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if the cam lobe ramp angle is not steep enough to
require the use of a roller to climb it.. there is NO gain from a roller.. ( if the cam lobe angle is steep enough it will try and push a lifter side ways... then you need a roller) but they are cheap..So why not put them in .. i would just for the hell of it and because I can... .
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09 XT660R ... 06 TTR250 ... 80 Montesa H6 125 Enduro... 77 Montesa Cota 348 MRR "Malcom Rathnell Replica"... Current resto projects.. 81 Honda CT110... 80 Kawasaki KL250A1... 11 Husaburg TE125 enduro... "sold" along with another 31... Lifan 125 Pitbike.. "stolen" ... KIWI BIKER FORUM...... http://www.kiwibiker.co.nz/forums/content.php All the best offroad rides in NZ... http://www.remotemoto.com/ E-mail... xtpete1@gmail.com |
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11-10-2018, 02:03 PM | #13 |
Join Date: Mar 2009
Location: Sardis, BC, Canada
Posts: 25,977
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I'm shy about using rollers, because the needle rollers are another point of failure. I've seen roller rockers grenade inside V8 engines, and those needles go places you don't want them. As Dan says, I'd be more interested in a different ratio.
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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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11-10-2018, 02:08 PM | #14 |
Join Date: Sep 2018
Posts: 173
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Can someone tell me why my rockers wouldn't be moving? Got the piston and new head installed(great compression etc...), and rotated engine with pushrods set in the rocker joints and they don't move.. Exhaust is really high up and intake really low, and cam is moving etc..
I have the rocker pin set with the bolt tightened I'm hoping I can fix this there instead of pulling up the piston sleeve. Even though doing work on the piston sleeve is surprisingly fast and requires no special tools. |
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11-10-2018, 04:31 PM | #15 |
Join Date: Jan 2012
Location: ChCh , NZ
Posts: 2,265
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are the push rods the same length ?
..
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09 XT660R ... 06 TTR250 ... 80 Montesa H6 125 Enduro... 77 Montesa Cota 348 MRR "Malcom Rathnell Replica"... Current resto projects.. 81 Honda CT110... 80 Kawasaki KL250A1... 11 Husaburg TE125 enduro... "sold" along with another 31... Lifan 125 Pitbike.. "stolen" ... KIWI BIKER FORUM...... http://www.kiwibiker.co.nz/forums/content.php All the best offroad rides in NZ... http://www.remotemoto.com/ E-mail... xtpete1@gmail.com |
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