larryhobman
Scoot Enthusiast
Posts: 117
Location: Delaware beaches
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Post by larryhobman on May 18, 2018 12:17:21 GMT -5
I recently installed a cheap Chinese kit that came with a head. You you guys talk about break in miles, is that the china mile or actual miles. I am at 100 China miles right now and need to know so I can tune my main jet. I am starting with a 98mj and 34 pilot pod filter and a A9 cam.
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Post by scootnewb on May 22, 2018 22:26:04 GMT -5
Sorry you got that bad advice. The compression with that BBK and a stock head is over 200psi. Sometimes way over. If you try to kick start it and it feels like there a solid rock in there....it's probably too much compression. Sometimes the electric starter can;t even crank it over. I ordered a compression tester. I thought it was some exotic expensive thing but it just a gauge that plugs into the spark plug hole.  I haven't ridden it since the learning of the dangers and I'll be installing an A-9 to help lower compression and add some power. What is a safe psi for a 50mm bbk and stock head? I've read 190 is optimal. Thanks |
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Post by dexameth on May 24, 2018 13:02:34 GMT -5
Kymco Agility 50 Service Manual calls for 200psi... weird because I thought my 205 was extremely high. I need to re-test mine now that it's broken in. larryhobman I did a new break in technique. I used to baby my motors for a few days, but then I started hearing motor builders tell me to rip on it out of the gate and seat those rings in. So I mixed it up. Motor was freshly built, never started. I fired it up almost instantly and let it idle for a few seconds to throw oil around then killed it. I then fired it right back up and went around the neighborhood giving it half throttle, then 0 throttle, then 25%, and so on. Every so often I would hold it at 50% then slam the throttle closed til I coasted to a stop... I did this for 10 minutes then went home and let it completely cool. Did the same ride for 10 minutes and called it a night. Next day I hammered on it, WOT runs but only for a few seconds. I did that for 2-3 miles then started driving it like I owned it for years. Been ripping on it for a couple weeks now. |
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Post by scootnewb on May 24, 2018 13:36:31 GMT -5
I've inadvertently been doing the same. I sometimes forget I am breaking it in and will go WOT. I still need to make some adjustments cause the 'blip-ing' came back. I'm trying to find something inexpensive and quick to check the CHT and I'm trying to motivate and install the A-9 cam but feel like shit today. There are also some strange noises I noticed when I let it warm up idling. It's hard to hear over that noisy pipe.  But I'm thinking the crank bearing or something  |
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Post by dexameth on May 24, 2018 13:38:58 GMT -5
Uh ohh... I hope not. I only did two "warm up" runs before I went WOT, but I did do the fluctuating like the builders were calling for. Don't hold one RPM for too long, bring it up, let it down over and over. Hunting noises can be a pain man...
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Post by scootnewb on May 24, 2018 13:48:53 GMT -5
Uh ohh... I hope not. I only did two "warm up" runs before I went WOT, but I did do the fluctuating like the builders were calling for. Don't hold one RPM for too long, bring it up, let it down over and over. Hunting noises can be a pain man... Yeah. it doesn't sound like valve clatter and it's not quite like a knock. I'll try to capture it on video. As long as the motor doesn't blow up or seize and cause an injury or throw me into traffic, I'm ok with it.  I really want to install a stroker and 52mm anyway. I've tried finding a Hoca BVH with 69mm valves but all I've seen are 64mm. Any ideas on where to get the right one? Is there a Hoca BVK that works with both 50mm and 52mm BBKs? |
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Post by scootnewb on May 24, 2018 13:56:10 GMT -5
I saw that dude kick starts you tube video with his 50mm bbk, thing was sounding and running awesome but it seems there's all kinds of trouble with his 52mm build so I was hoping I could just copy your build (or is that not cool)? I don't have enough experience to mix and match high performance parts.
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Post by dexameth on May 24, 2018 13:57:38 GMT -5
I really want to install a stroker and 52mm anyway. I've tried finding a Hoca BVH with 69mm valves but all I've seen are 64mm. Any ideas on where to get the right one? Is there a Hoca BVK that works with both 50mm and 52mm BBKs? It's for 52mm This is the 50mm head (but the 52 could possibly work). SSP-G is Hoca. Hoca's owner retired, and took the name with it so we changed the name to SSP-G. Same Taiwanese foundary, AWESOME QUALITY. Don't worry about the valve length. The only thing you'll need to change will be the rockers to match the valve length (if yours are 69mm now). |
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Post by scootnewb on May 24, 2018 14:07:36 GMT -5
Yes mine are 69 now. How bizarre, I have always been told you have to check for 69mm or 64mm valve size on the stock head and make sure the replacement head has the same. I didn't know it was just a matter of rocker assembly preventing them from being interchangeable. So you are 'partsforscooters.com'? Please create a 'dexameth' BBK package.  It looks like the high quality parts will be about $600 to make it all happen. |
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Post by dexameth on May 25, 2018 10:31:39 GMT -5
Here's a parts list drawn up of EVERYTHING I used for my build. Highlighted in green is for the bare minimum, and omit the first part if you don't want to use a stroker crank. 10% off sale running this weekend on the website too!  |
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Post by magoconnor on Aug 19, 2018 18:05:21 GMT -5
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Post by V90Performance on Aug 20, 2018 4:59:12 GMT -5
A year later, 5000 miles on my Naraku 52.4mm bbk.
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Post by KSR Moto on Aug 20, 2018 8:27:22 GMT -5
A year later, 5000 miles on my Naraku 52.4mm bbk. Which crank did you used? |
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Post by katt on Aug 22, 2018 7:39:01 GMT -5
Heck, even improper torquing of the head bolts might cause oil problems the way these motors are designed. How's that possible? |
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Post by KSR Moto on Aug 22, 2018 10:26:32 GMT -5
Heck, even improper torquing of the head bolts might cause oil problems the way these motors are designed. How's that possible? Quite easily actually, you should always use torque wrench for head |
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