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08-26-2020, 06:05 PM | #1 |
Join Date: Aug 2020
Location: Australia
Posts: 1,408
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Poor Mans Pool Noodle Cylinder Hone.
Hi, Was going to put this in my XL185 with a Zongshen CG250 swap project thread but I think this information is general purpose DIY maintenance that might help.
My used CG250 had weak compression so I removed the top end to find a fair bit of piston slop and a glazed bore. Clearly it was burning oil. I checked Aliexpress, piston/ring kit was $25AUD and a new Jug/piston/ring kit was about >$100AUD (shipped) I decided to try the low cost approach first so went with piston/ring kit went with this... https://www.aliexpress.com/snapshot/...ctId=752466407 So what to do about the glazed jug... purchasing a 3prong or dingle hone would defeat the cost saving by not getting a new cylinder kit. Ive seen people use red scotchbrite but I wanted something more consistent. So looking around my home MacGyver style, I found a section of pool noodle, some masking tape, a sheet of 600grit wet dry sand paper and some lube oil (whatever you got) (Disclaimer) this will work on any small engine cylinder to de glaze and apply a cross hatch. It is not a hone to re bore... Process: 1. wrap the noodle with tape sticky side out. 2. roll the sandpaper around the noodle. Half a sheet was enough for me. 3. lube the sheet and cylinder and insert your hone* 4.by hand using a IN and Twist / OUT and Twist action. clockwise/anticlockwise doesn't matter but be mindful of the sandpaper sheet overlap. 5. Check results every half a dozen or so turns. 6. When you have achieved the desired result you're done and now your new piston rings should seat properly. Remember this is just a poverty spec solution. Do so at your own risk. Cheers, XLsior |
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08-26-2020, 06:12 PM | #2 |
Join Date: Aug 2020
Location: Australia
Posts: 1,408
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Sorry The Aliexpres link didn't work but it was listed as a
Racing Molybdenum 65.5MM 15MM Piston Ring Gasket Kit CB250 CB200 200CC 250CC 165FMM ZongShen Loncin Dirt Pit Bikes Motorcycle I measured the diameter of my original piston before ordering to check it wasn't a 67mm |
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08-27-2020, 02:01 AM | #3 |
Join Date: Aug 2020
Location: Australia
Posts: 1,408
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Additional Notes:
The ball and 3 prong store bought hone sets appear to range from 120grit to 320 grit. So my 600grit wet dry sand paper is mild in comparison. 400grit might be a better choice. however due to this it is very unlikely you will cause any damage. Also I believe the optimal cross hatch angle is 45*, so you will have dial in your own IN and Out Twist action to achieve something close to this. |
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08-27-2020, 11:12 AM | #4 |
Join Date: Mar 2010
Location: Volcano, Ca
Posts: 7,112
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Genius! Love it! This is the true essence of being a China Rider, if I've ever seen one......
Congrats on the great (and dirt cheap) solution! Oh....and I love the self-draining workbench. ;-)
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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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08-27-2020, 04:57 PM | #5 |
Join Date: Aug 2020
Location: Australia
Posts: 1,408
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Thanks 2LZ,
I put creases in clothes, ain't got time to iron them out. |
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08-27-2020, 08:26 PM | #7 |
Join Date: Mar 2008
Posts: 2,436
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65.5mm (15 pin) 223 is not a typical CG config
The altenative http://chinariders.net/showthread.php?t=14466 if can't find from elsewhere. The offical consolidation service https://world.taobao.com/helper/know...m?&kid=6551702 to OZ https://item.taobao.com/item.htm?id=608837686639
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08-27-2020, 09:00 PM | #8 |
Join Date: Aug 2020
Location: Australia
Posts: 1,408
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Hi Humanbeing,
you are correct it is not typical. My engine is marked ZS167FMM... which would indicate a (1)single cylinder ans (67) mm bore. But as we know this is China manufacturing. It really would be a CG230* This is why it is important to measure the piston before ordering a replacement. The cylinder, piston and wrist pin from my engine match the dimensions in your provided image. |
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08-27-2020, 09:09 PM | #9 |
Join Date: Aug 2020
Location: Australia
Posts: 1,408
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Actually I measured the cylinder height to compare.
there is a difference 29mm/33mm and 76mm/80mm. Conclusion: China |
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08-27-2020, 11:11 PM | #11 |
Join Date: Aug 2020
Location: Australia
Posts: 1,408
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Good to know.
153mm push rods confirmed. 250cm3 cylinder with a 65.5mm piston. I still advise measuring the piston when all you decide to do is purchase a new piston and rings and hone your existing cylinder. |
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08-28-2020, 11:36 AM | #12 |
Join Date: Mar 2010
Location: Volcano, Ca
Posts: 7,112
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humanbeing is like our version of Yoda. Has all the info and shows up when needed to spread his wisdom. ;-)
__________________
"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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08-28-2020, 05:51 PM | #13 |
Join Date: Aug 2020
Location: Australia
Posts: 1,408
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I double checked the wrist pin measurement as Humanbeing suggested my engine was weird config.
Pretty sure it is a standard 67mm with 16mm pin. the wrist pin size is what thew me... I have adjusted my intended piston order and have also purchased as set of digi measuring calipers to avoid any more miss measurements. It's why sharing this sort of information helps everyone. Catch these kind of mistakes before they are made. |
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