YX160cc into 191ccBeast Am I crazy?

Advertise with us
Find deals on amazon
Shop deals on ebay
Mini Dirt Bikes & Pit Bikes Forum

Help Support Mini Dirt Bikes & Pit Bikes Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Wow 200c motard would be fun. I am just going to running 2 heavier springs like I have been in the 160cc.
Sean did you have to bore the case to fit 65mm barrel. I am under the impression I will have to to this becuase 64mm is the limit.
Ride on DD
 
I hope so have to wait and see, barrel you be here tomorrow I hope.
Good night all I am out of here, till tomorrow.
Ride on DD
 
tbolt 184 4 valve head

hey im buliding my second pit bike with a 155z engine was just wondering if any 1 in aus was running the 184 4 valve setup from tbolt usa if any 1 is could u let me no how it compares to the big bore v2 kits thanks
 
dont bother with the cheap 4valves

From what i have read , they barely make more then the stock yx/z heads..

v2 out flows it easily
 
no, cheap 4valves just dont perform full stop. even a full ported 4 valve gets smashed by a mild ported v2
 
another downfall is apparently there are no camshafts available for them apart from the one supplied in the kit
 
update...
my mates 155z with the 65mm bore and 59mm stroke just had to replace his clutch basket. about 15hrs on it now
flogged the dampeners out
 
The stuff is here.

Hey all. Just got the V2 head and the 65mm barrel and akunar piston today.
Should have it built by the weekend. Have to bore the case's 1mm first then slap it together.
I have not seen one of these broken clutch baskets myself yet, but that is a huge motor 65 by 59mm. Things can brake on any motor so I am not worried, will just take it as it comes. Got 3 spare clutch baskets anyway off lifan motors with stuffed gear box's.
Plan to race my new beast at kurri kurri in june. Can't wait.
Ride on. DD
 
wrong size pin.

Got the barrel to fit the cases today. Spent all day boring cases by hand. Then when ready to install piston find out that a 13mm pin from a stock piston is to long for the akunar piston. So I have sent Damojay an pm to try and get the original pin i think he forgot to send me.
Bummer more waiting. Guess im riding the 150cc this weekend.
Ride on.
 
on a tight buget so have done case's by hand with a dremel to help. The 65mm barrel sleave is very long 4mm longer than the stock barrel sleave. It gets very close to the crank. I am getting 7mm cut off the end of the cylinder sleave so only 12mm will enter the case's solving clearence problems.
Ride on.
 
The beast is breathing fire.

Finally finished this project this morning before work. Had to get a yx gudgen pin shortened slightly to fit the akunar piston becuase the guy i brought off forgot to send pin.
Had just enough time to run it for 10 miniutes and do a couple of laps of my track this morning. The V2 head is ported to the max with S25cam and The TB decomp works great started pretty easy runing 26mm oko flatside at the moment with 98main and 36pilot. Will do a plug check soon, but it sounds and revs perfect which surprised me as other people seem to be runnning bigger jets in the states on such a build.
Wow it was so worth it. You can crack the throttle as quick as a 2 stroke and the overall torque is amazing. Pulls up hill harder than ever with no clucth slip, just running heavier clutch springs has got the 5plate clucth working great.
Lets hope it last. Ride on.
 
Nice work . you will find it will get real hot after a few high rev runs with a 98 main.

I went to 102 and it doesnt get half as hot . and improved topend slightly .

Sean reckons you can go alot higher main then that to.
 
Cheers bro I was thinking 105 for the main jet, and probably a 38 pilot, but no I am thinking a wont have to change the pilot as the clip is second from the top at the moment. Any comments appreciated.
Ride on
 
Are you running a 26mm or 28mm oko?
 
You must log in or register to reply here.

Latest posts

Back
Top