help me with mods

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dabigbratj

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ok just got a 350 well i get it next week.but I'm gonna order exhaust intake and jets
first off where can a get a 12:1 piston and a good cam I'm looking to get a cam as well looking for one with good low to mid range power let me know best places to get these parts ;D
also wondering where to get a big bore kit for it as well a good reliable build
 
From what I read, you'll probably need to run a mix of race gas for the 12:1, I would go for the wiseco. The web .390 lift cam would be perfect for low to mid power.
 
With 12.1 compression you need a bigger cam. If you go onto www.powroll.com they should have everything you need. They have the full race cam that will work with their piston, it's a .430 lift cam with 288° of duration, or www.megacyclecams.com they have a.450 lift cam with 276° duration. Also check out www.fourstroketech.net and www.cycleworksracing.net

http://cgi.ebay.com/ebaymotors/YAMAHA-YFM-350-WARRIOR-JE-PISTON-STD-BORE-12-1-87-04_W0QQcmdZViewItemQQ_trksidZp1638Q2em118Q2el1247QQcategoryZ43977QQihZ018QQitemZ280163708590QQrdZ1QQsspagenameZWD1V
 
ok will i need to modify the head at all for the cam or can i just put it in ill prolly get hd springs as well.
also what would valves need to be set at with this cam and what kinda gainsw would i se from full exhaust intake no lid 12:1 piston and that cam?
 
ok will i need to modify the head at all for the cam or can i just put it in ill prolly get hd springs as well.
also what would valves need to be set at with this cam and what kinda gainsw would i se from full exhaust intake no lid 12:1 piston and that cam?

I would buy the piston from ebay definitly, if you don't want to bore it and the jug looks good just get the standard bore 12.1 JE, If you need or want to bore the jug, JE has the 2mm over 12.1 for 366cc engine. With that piston I would get the Megaycle .450 cam, and springs. The head don't need to be ported although it'll help greatly in the breathing dept. BTW if you do get the head ported they will modify the combustion chamber which will help it be less detonation prone and you may only need race fuel in the worse heat of the summer. The cam comes with a cam card and the valve adjustments will be on there. Standard adjustment is .004mm I, .006mm E


With all that this motor will make a good 34HP, plus will be a nice rever.
 
i have some kibbie white hd springs and the retainers i also have a cam but think i wanta hold on to it for now but will sell ya the spings and retainers cheap. if your near Peoria go to Southard Cycle
(309) 682-3367 at 3324 Ne Adams St, Peoria, IL 61603 for head work and bore and or hone.
 
Yeah I would go with the 12:1 JE piston. Either standard size or 2mm overbore is your choise if the cylinder is good for the standard.
I would look at getting the Megacycle 252x2 (all around power) grind cam which is more for maybe what you are looking for. More bottom end and mid range power.
 
on the 12:1, can you just run a mix of race gas with the ported chamber if so, what would be a good mix?
 
on the 12:1, can you just run a mix of race gas with the ported chamber if so, what would be a good mix?

50/50 bend from high test is what I've heard. Straight sunco 110 I bet would work really good. I would hate to have to do a trail ride and only have 87 around when going past 100 mile trips.
Basically you open the combustion chamber up around the valves to so as when the valve is opening air flows easier around the bends. A person that does this will usally also tend to take a little off of the head to bring back the combustion chamber volume. Also be noted though that it is not much they will take off around the valves and maybe lower a combustion point by .1.
 
FST is a big one that comes to mind on port and flowing the warrior head for cheap and does it very well.
 
ok thanks jason, i planned on doing 50/50 it will be a pain in the ass but not too bad for the extra power i guess, I just want to run a race cam but also not lose too much lower end on the bike as it is used a lot in trails
 
that would make up for it. The engine is going to run really hot so make sure and have a oil cooler. Make sure the rod bearing is good as well.
 
ok ya i will like to get an oil cooler as far as rod bearing??? i dont know it is stock, if it goes out, stroker goes in lol
 
is there any way to check rod bearing? does octane booster help out any on the gas?

No it doesn't help at all.. maybe a couple points by tenths. You can't use AV fuel either. Were talking the expensive **** like 8.00 dollars a gallon sunco 110-115 octane drag racing fuel.
The way to check the rod bearing is when you have the piston off is to measure the movement of it up and down and side to side.
I check this when I put my piston in and it measured fine, its on its way out now.
 

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