Pcx Yuminashi Chainsaw 164!

[Pcxdemon]

A Gift from mr Yuminashi http://i1228.photobucket.com/albums/ee4 ... bqmkvk.jpg

[waspmike]

Cant reply a pm from waspmike.... Ill show you what happend to the jcosta The copper central ring wore off and the slided off the variator im expeting a replacement ring from jcosta

http://s27.postimg.org/wu3qfo5kz/IMG_20 ... 091849.jpg

i think you might need 20 posts or something before you can send anyone a PM.

They are called "bushing" they have to be pressed into the pulley half.

let me know if you have any problems.

[sergiopatron]

Got the jcosta ready and installed the 44T final gear... On the first run with the stock vario it felt very fast but it still reads 108 before the rev limiter kicks in.... Lately when im crusing at 80 and open the throttle theres a power loss feels the engine is ideling?? Wrong AFR ratio? Any ideas?

[lolofigo]

Got the jcosta ready and installed the 44T final gear... On the first run with the stock vario it felt very fast but it still reads 108 before the rev limiter kicks in.... Lately when im crusing at 80 and open the throttle theres a power loss feels the engine is ideling?? Wrong AFR ratio? Any ideas?

[lolofigo]

Hi I'm thinking about changing final gear to 44t sprocket from yuminashi. It says on their website that 45/15 set requires longer speed sensor but nothing about 44t sprocket. Anyone has any experience with that?

[lolofigo]

Hi I'm thinking about changing final gear to 44t sprocket from yuminashi. It says on their website that 45/15 set requires longer speed sensor but nothing about 44t sprocket. Anyone has any experience with that?

Well no one responded so I bought it anyway. My findings are:
-sprocket is same diameter but has less teeth so they are bigger and there is more free play in the transmission
-original speed sensor is working well
-better reaction to throttle in speeds over 40 mph
-according to yuminashi speed indicated on the clock is more accurate and speedo shows actual GPS speed but haven't got time to run GPS test
-top speed on original sprocket was 60 mph GPS now is 60 indicated by speedo the same. I think bike has longer gearing but no power to push it over 60 mph.
I guess yuminashi essential kit is going in next

[proteinsdef]

I wondered if anyone had any reliability info on this setup?. I am keen to carry out the mods, but if it needs rebuilding every few thousand miles, I wont bother, especially when the Honda unit is so reliable!

[BPT7594]

I wondered if anyone had any reliability info on this setup?. I am keen to carry out the mods, but if it needs rebuilding every few thousand miles, I wont bother, especially when the Honda unit is so reliable!

Reliability is good. I have a kit currently on my friend's PCX 2010 that's 11k km and still going strong without any oil leak because of worn rings, overheat or anything like that.
Be sure to change oil more frequently though, because a higher cc engine tends to run hotter overall and oil will lose its quality sooner. I change my oil every 1000km, got a good brand of synthetic oil that's relatively cheap over here.

[proteinsdef]

And is there any issue with them overheating in general? Do you have to modify the cooling system?

[lolofigo]

Just go for it. For the price of sports exhaust from webike or ebay you'll get completely different bike. Keep old parts if you worried about reliability so you can always come back to old setup but you'll never look back. Big bore kit gives more smiles per gallon for sure.

[BPT7594]

I installed a SH150 cooling fan on my rotor, has a yuminashi 1.6 bar radiator cap coming.
I plan on using a 8 part water 2 part antifreeze coolant mix too.
Or just run plain water. Plain water has the best cooling capacity.
It does run hotter though. Don't expect it to be as cool as stock, especially with the 27/22 valves from stock cylinder head. I'm running 29/23mm valves. Bigger valves and hot cams traditionally mean lower temperature engine.

[proteinsdef]

It just all seems a little gung ho for me and a case of try it and see what happens kind of philosophy. I use the scoot as my main point of transport and need rock solid reliability as well. I don't like the idea of putting in simple water, as in the UK, the block will split straight away as soon as the sign of winter appears.

Might just stick to my basic mods until I can afford the bigger bike for kicks. Thanks for the input though guys.

[BPT7594]

It just all seems a little gung ho for me and a case of try it and see what happens kind of philosophy. I use the scoot as my main point of transport and need rock solid reliability as well. I don't like the idea of putting in simple water, as in the UK, the block will split straight away as soon as the sign of winter appears.

Might just stick to my basic mods until I can afford the bigger bike for kicks. Thanks for the input though guys.

You can use 5 5 water vs antifreeze.
I'd say spending money on big bore kits is mostly for the sake of fun and tuning.
If you like stock bikes, get a bigger bike. Me I like tuning and fiddling, so I buy big bore kits and try to improve a smaller bike. It's the fun of tuning

[Pcxdemon]

New cylinder design with high comp piston and yuminashi 150 head.

http://i1228.photobucket.com/albums/ee4 ... z7mkry.jpg


http://i1228.photobucket.com/albums/ee4 ... db0bdu.jpg

http://i1228.photobucket.com/albums/ee4 ... rzkpij.jpg

[k2apache6.0]

Great thread here, loving it. Who knows, maybe I'll try it before years end. Keep the info and impressions coming. BTW there's a 170 Nikasil big bore kit on ebay, no idea who makes it but it's cheap...
http://www.ebay.com/itm/170cc-cylinder- ... zn&vxp=mtr

[Pcxdemon]

I like yuminashi 60mm cylinder because it has more meat between burning chamber and a water ports. It's less prone to have a failed Headgasket. I feel that 170cc or 61mm bore is too thin to take a chance. Besides power between the two is same.

[Pcxdemon]

Variators from left to right: yuminashi, mfr2, Daytona and takegawa

http://i1228.photobucket.com/albums/ee4 ... 3qtotd.jpg

You can see yuminashi where rollers/sliders use all of ramp profile others never really do..

http://i1228.photobucket.com/albums/ee4 ... meqb70.jpg

http://i1228.photobucket.com/albums/ee4 ... e7iwyy.jpg

http://i1228.photobucket.com/albums/ee4 ... 43i6dn.jpg

http://i1228.photobucket.com/albums/ee4 ... heodji.jpg

Also check out yuminashi design where it gets super close to outer pulley because of the milled centre enabling to push the belt right up for increased top speed...

http://i1228.photobucket.com/albums/ee4 ... inhthk.jpg

[Srazo]

Hello, mates!
How is your cam performing, Mgalutia88 ? Do you feel the income?

I am waiting for the parcel with the 190cc whole kit from RZracing, it will arrive day to day.. I feel nervous, don't know am I right to mess with modding.. Hope everything will go right and smooth..

Can you direct me to where I can find the rzracing 190cc kit you purchased? I can not find the site, possibly because I'm in the US maybe? Any help would be great.

[WhiteNoise]

Hi Srazo, I see you've requested some info from member Pcxdemon. I also see that his last post on this thread was 2016. And I also see that you only have 1 post on our forum(s).
As per forum rules, a member needs at least 15 posts before they can send a PM (private message),

I encourage you to keep on posting so that feature can become yours

WAIT!! Some Good news! I went ahead and pm'd Pcxdemon for you and pointed him to this thread. In the meantime go on and cruise around, enjoy a bit of chatting - while we wait for His return.

Oh, here's something you can do for the Forum (haha, and just when you thought it was That easy )
We'd like you to add your location to your profile. I have easy directions posted below to guide you. Adding that wee piece of info will help us to help you, now and in the future. Seems we always have questions...right?

Shout-out to Pcxdemon......can you hear me now????

[Pcxdemon]

Im Here!!
My advice is to get the Takegawa kit from webike, forza 300 throttle body from partzilla site(chameleon throttle body to head manifold on webike site), exhaust (takegawa from webike again), mfr sports 2 variator with 14degree face pulley and mfr stiff clutch side spring and last but not least a bigger injector (i think mine has 6 holes) from yuminashi..

with takegawa kit, separate the headgasket as its tripple layered and from experience lowers compression too much but does keep the temps slightly cooler though but performance suffer. I just use single layer of the gasket and its spot on compression as performance response is on point,temps slightly higher but ok and never give me issues. My water temp sits on 88-89c riding and 92-93c ideling at traffic lights. anything bellow 95 is sweet. Trouble starts 100c plus. Oh and get the 1.6bar radiator cap..

Gotta run,running late..

thanks white noise..