|
|
Post by magoconnor on Jan 22, 2019 21:49:17 GMT -5
Hello.
Can anybody help find a racing camshaft of lasting quality, I have been looking all over with no luck.
I'm not looking for a touring version, but rather one that helps the engine breathe at high rpms.
cheers mag.
|
|
|
|
Post by dexameth on Jan 23, 2019 13:34:15 GMT -5
magoconnorWhich engine are running this new cam on?
|
|
|
|
Post by magoconnor on Jan 23, 2019 14:41:19 GMT -5
My bad...
Its a 139qmb + 90cc naraku kit.
20mm carb.
Open air filter.
leovince exhaust.
+ thousand other parts.
|
|
|
|
Post by magoconnor on Jan 23, 2019 17:29:59 GMT -5
Okay so I might have found one.
Its made in taiwan so thats good, the seller also listed some specs on it.
Camshaft
- 26.30mm intake (against 25.73 of original)
- 25.90mm exhaust (against 25.55 of original)
Can somebody tell me what this does differently, compared to the original?
|
|
|
|
Post by dexameth on Jan 24, 2019 9:16:06 GMT -5
Dang! Those are some high-lift lobes. Curious as their timing (really hard to tell timing without dial guages and whatnot). Our SSP-G Cam Specs: Intake: 25.7mm Exhaust: 25.6mm The lobes are timed earlier for intake and longer duration (thicker lobes) and later on exhaust with a thicker lobe as well. This design was intended to protect piston-to-valve clearance. The early timed and thicker lobes keep the valves open longer to breathe more. The cam provides a great power increase from low to high rpms, and is more "grunty" than the A9 cam in the lower rev range. I've tested both, settled on the SSP-G. The specs you provided seem much higher lift (which in theory allows more flow) but may have clearance issues. Do you have a link to the cam you are mentioning? |
|
|
|
Post by dexameth on Jan 24, 2019 9:19:18 GMT -5
And you know, you are set up to run a 24mm CVK carb if you want more power as well. Pair a stock GY6 intake with a 24mm stock CVK carb (the ports match up pretty dang close) with the Naraku spacer under the intake and you'll have some power increase... I promise. |
|
|
|
Post by magoconnor on Jan 24, 2019 17:01:52 GMT -5
Yeah I have thought about it, and I already got the naraku spacer.
Have you installed your portet cylinder head yet?
Not sure if you show it, but did you clean up your combustion chamber to?
|
|
|
|
Post by KSR Moto on Jan 25, 2019 9:18:09 GMT -5
|
|
|
|
Post by dexameth on Jan 25, 2019 9:28:55 GMT -5
Yeah I have thought about it, and I already got the naraku spacer. Have you installed your portet cylinder head yet? Not sure if you show it, but did you clean up your combustion chamber to? Yeah, it's on. And it's a noticeable difference for sure. It's snappier, and revs up quicker. I'm having carb issues, my diaphragm is swollen and feels like it "flutters" at WOT. I kinda lose power and regain it at random, but only a tid bit of power fluctuates. I feel like the slide is not opening fully... when I take the carb cap off to adjust the needle the diaphragm is always larger than the carb... thanks ethanol. With the combustion chamber I just run a wire brush in a power drill and brush it clean. I did lap the valves after I did the porting, wanted a better seal. I can't wait to get this carb issue figured out, have spares to install after work today. |
|
|
|
Post by magoconnor on Jan 25, 2019 12:40:36 GMT -5
Cool, I think im gonna do the same  By cleaning up the combustion chamber I meant, removing the sharp edges around the valves. Im a little unsure if i should do it or not. Im afraid to lose compression.. |
|
|
|
Post by dexameth on Jan 25, 2019 13:53:46 GMT -5
Yeah, I love the Hoca (SSP-G) 52mm head, it has an improved combustion chamber over most big valve heads. I don't wanna touch it to mess up the design haha
|
|
|
|
Post by magoconnor on Jan 25, 2019 16:37:41 GMT -5
What size are your valves?
|
|
|
|
Post by fugaziiv on Jan 25, 2019 16:41:27 GMT -5
What size are your valves? Intake Valve Diameter: 21.5mm Intake Port Diameter: 24mm Exhaust Valve Diameter: 18.9mm Exhaust Port Diameter: 22mm Matt |
|
|
|
Post by dexameth on Jan 25, 2019 16:41:37 GMT -5
21.5 intake, 19 exhaust. I used a 52mm head with bigger valves (23/21), but the porting was HORRIBLE (SMM brand, eBay seller). Like really tiny ports. I could have ported them open more, but I was a newbie and honestly afraid of it. This Hoca head really needed no porting, I just cleaned it all up, and opened it up just slightly. I did open the exhaust port a bit though, gave it more of that cone shape. The eBay head also had a larger combustion chamber bringing the combustion pressure down a bit.
Edit: I guess my exhaust port is 24mm now with my header pipe at 25mm (almost matched)
|
|
|
|
Post by fugaziiv on Jan 25, 2019 16:53:31 GMT -5
21.5 intake, 19 exhaust. I used a 52mm head with bigger valves (23/21), but the porting was HORRIBLE (SMM brand, eBay seller). Like really tiny ports. I could have ported them open more, but I was a newbie and honestly afraid of it. This Hoca head really needed no porting, I just cleaned it all up, and opened it up just slightly. I did open the exhaust port a bit though, gave it more of that cone shape. The eBay head also had a larger combustion chamber bringing the combustion pressure down a bit. Edit: I guess my exhaust port is 24mm now with my header pipe at 25mm (almost matched) Oh you fancy with those ported... uhh... ports. Matt |
|
