Predicament on what top end to run

[Wilksy]

Ok so bit of a story but bare with me

Purchased a 2000 yz250 for a project with seized crank a while ago, full rebuild, powdercoated frame, full overhaul of motor,transmission etc as everything was stuffed... 

So im at the stage now where the bottom end is together and im trying to work out what path to go for the top end. 

Now problem i have is the barrel had been steel sleeved by previous owner... really badly, it hasnt been matched so ports are all crappy and powervalve wont close completely due to interfeering with sleeve, so im scrapping that barrel

Now comes the esr 325 big bore kit, it appeals due to the fact it comes as a complete bolt on kit including the barrel

Other option is to get a 2nd hand barrel a send it off to two stroke performance in australia to carry out there 295 big bore kit a porting. 

 

Bare in mind im not a proffesional and the bike will be used for mainly trail riding, beach, and just playing around. Im worried with the big bores il loose that snappy revy 2 stroke feel? 

I am in australia so its hard to have contact with the big names in america that do top end work. Ive searched and read so many threads in regards to the 325 kit on this forum i think ive confused myself even more haha 

 

[rpt50]

Can't you just get another jug?  That seems like the easiest route.  Did you ever see a thread on big bores where someone did not have any problems?  

[kxrob]

Wilksy where you at in oz mate ?

im in Queensland 

TSP might be your best bet for a big bore and if you have any problems then there close by instead of a 17 hour time difference 

PM numbroe on these forums, he has a 295cc yz in oz and he can discuss head squish as well ( tsp can do the mod ) , if you want to talk carb tuning pm me or numbroe and we can give you part numbers for the magic Suzuki needles ( these are what tsp use as well )

Edited April 1, 2017 by kxrob

[Wilksy]

I have sourced another barrel but just unsure what route to go, i could however send this jug off to be ported and all the biz by tsp and most likely have the same output as the 325 but with slightly less torque with standard 250cc capacity 

 

[Wilksy]

Thanks kxrob for reply.. im located down in tassie, i did phone tsp on friday but seems he is a very busy man and could only talk to his office lady, i am leading towards tsp at this point purely for the local factor and he does alot of research snd developtment aswell. 

[jamracing]

For just messin' around, i'd keep it stock with a good port and head job. No muss, no fuss, lasts forever

[projectcxr]

You get out of everything what you put in. A 2T engine is exactly that, and unless you are pretty handy with a die grinder and are steady and well versed with 2T engines, don't buy an off the shelf big-bore kit. Get Dave at TSP to build you what you want.

However if you want the satisfaction of building a brilliant versatile and very flexible all terrain engine buy the ESR 325 raw parts and go from there.

[Wilksy]

Have decided to send my top end to tsp for the works. Alot of money but i believe will be worth it. Cant wait to finally have this bike back together and finished