A few power mods (Nice HP gain)

[Ride1Rob]

For the past few days I've been tearing Jams bike down to check on things. I had some parts coming in so I took the time to tear into this motor to check on some things. Almost everything was still in good condition ;) . The stock piston had heat marks in one small area but the cylinder looked almost brand new. I upgraded to the bigger Aluminum oil cooler to keep the bike running cooler and I also installed the HC piston. To help to maximize the piston I ported and polished the head. This stock 125 head is VERY restricted and I couldn't even get my thumb through the intake port :ermm: . Once I saw this I knew that porting the head along with the piston would do wonders for this motor. I finished everything today and let me tell you :eek2: ... This bike performs wayyy better than it did before the mods. With the added power it's more noticeable that the clutches are slipping once again. Stock, the bike wasn't pulling as hard rounding corners in higher gears so it wasn't noticeable. I'll end up going with the full TRX90 setup as I've heard some good things about the setup. From 1st to 4th gear the bike pulls and runs stronger and I still haven't dialed the jetting in for better performance as of yet. If anyone is considering doing mods to this bike this is surely a way to go for nice HP gains. I'll post a few pics of the portwork that I did and once everything is dialed in I'll post before and after vids...

Stock pics....
http://img8.uploadhouse.com/fileuploads/2226/222672872cf9c768f2d4ef22f0b4d8800ada4e8.jpg (http://www.uploadhouse.com/viewfile.php?id=2226728&showlnk=0)
http://img5.uploadhouse.com/fileuploads/2226/2226725dce7bad051951511794416135df73b48.jpg (http://www.uploadhouse.com/viewfile.php?id=2226725&showlnk=0)
Look at how restricted the intake port is...
http://img3.uploadhouse.com/fileuploads/2226/2226723295871ee7ca00390284b401e67cdaeca.jpg (http://www.uploadhouse.com/viewfile.php?id=2226723&showlnk=0)

Pics of head after porting/polishing...
http://img7.uploadhouse.com/fileuploads/2226/2226787acb5c187a727f5d51065b214e53c251f.jpg (http://www.uploadhouse.com/viewfile.php?id=2226787&showlnk=0)
Exhaust port cleaned up and all obstacles removed for smooth airflow to header...
http://img6.uploadhouse.com/fileuploads/2226/22267866739eea8cf1549e4684694bd9da86df6.jpg (http://www.uploadhouse.com/viewfile.php?id=2226786&showlnk=0)
Intake port took the most work b/c of how restricted it was...
http://img9.uploadhouse.com/fileuploads/2226/22267291f3c4c695686221d44355460eec128ee.jpg (http://www.uploadhouse.com/viewfile.php?id=2226729&showlnk=0)

[double d 1]

i put the crower g2 cam and hc piston in my sons and he took it down the street. he said it felt better. i weigh 265, so i wouldnt be a very good judge. the one or two times i rode it, it started slipping in third gear. i was wondering on the pins that slide down the four cylinder/head studs. where do they go? i cant seem to find the right answer. i forgot to put them back on now i have to take it back apart. im going to put the 146 kit in when i do this. thanks for any help.

[Ride1Rob]

If you don't open that intake and exhaust port up it's not going to make as noticeable of a difference. You need to open up those ports to help get the best performance from the HC piston.

I wish someone made a better gasket kit as the one that I ordered is nothing more than thick paper. I have to loosen Jams head up and check his base gasket because of a small oil leak. His head gasket was the only thing worth the whole kit in the packet.

Found this pic... The pens sit in grooves similar to these ;) .

http://img4.uploadhouse.com/fileuploads/2246/22462343b328474ac14350d4ba93bec7cb36956.jpg (http://www.uploadhouse.com/viewfile.php?id=2246234&showlnk=0)

[double d 1]

two go on the cam chain side but wasnt sure between the head and cylinder. i'm wondering about the base gasket to. i had leaks the first time and took it apart and it was torn. the second one seems to work. xtreme uses a honda style stud pattern except for the 125. i've been told after the fact that the 125 uses a chinese stud pattern, a little bigger spacing. makes me wonder if these 125's need a differant gasket. i'll do some checking. thanks

[JBOYZ]

You will get even better performance if you go with a "big-valve" head.... :rolleyes: Xtreme didn't leave enough room to do much work on the valves....

[Ride1Rob]

Originally posted by JBOYZ
You will get even better performance if you go with a "big-valve" head.... :rolleyes: Xtreme didn't leave enough room to do much work on the valves....

How much performance can be gained from the big valve head? Let me know if you have them in stock and how much they run...

[double d 1]

found out that the gasket kit the xtreme dealer sold me is the wrong one. the right one is tb55mm gasket kit. the dealer sold me the tb54mm which is for a 125 but with honda stud spacing. tbolt usa has these kits.

[leager-n-ky]

Hey Rob, You said you went with the trx 90 clutch we did that last season and it hooks up great we just cant get it adjusted to where he can do a neutral drop of the line any suggestions on that??

[Ride1Rob]

Originally posted by leager-n-ky
Hey Rob, You said you went with the trx 90 clutch we did that last season and it hooks up great we just cant get it adjusted to where he can do a neutral drop of the line any suggestions on that??

I've been in contact with JOYZ who told me about the TRX and they are quite familiar with it. As of now I still haven't installed the setup in the bike so I'm not familiar with as of yet. I'm still waiting on a tool to remove the clutch assembly. Should be here tomorrow. I'm sure that it's something with the adjustment. Hit them up... 618-758-3500