Hard to go wrong with the V2 head and 65/66mm Wiseco in a steel-sleeved jug. 182/188cc handles most bigger tracks nicely, without wearing out the kit or your shift toe. Even the 64mm TB kit is a great setup.

 

well i found a kit that i want but im not sure how much HP it will produce and if it will fit the klx motor please help me out with this. heres a link to the kit.and does it mean that the cyclinder come with the kit?



YX 4 Valve Race Head and 62mm Bore Kit

 

You'll need a LOT of Dr Guff's to make any real power with the Kit-knocko 4v head.

Small valves, poorly shaped ports with Honda mounting, spotty QC, need for shims to adjust valves, and while a chopped-down 2v YX cam helps, the dyno says "turd". Might do OK in the dirt drags, though...



The trail bikes kit is the way to go, if budget is an issue.

 

That 4 valve head is plain and simply JUNK in stock form, your better off saving up for a Takegawa or Kitaco 4v kit.



Stick with good parts if you want the engine to last for a while. The V2 and Weisco full skirt piston that Terry is talking about is way to go in my opinion.

 

what about this

Honda Trail Bikes

and 55mm stoker crank?

 

what about this

Honda Trail Bikes

and 55mm stoker crank?

The trail bikes kit is by far the best bang for the buck, very reliable and plenty of power for your needs.

This kit comes complete and has everything you need, case boring is the only thing left to do.

 

so i should be good on big tracks with this kit right?

 

so i should be good on big tracks with this kit right?

Yes, with the right gearing and suspension , you will have alot of fun on the big bike tracks.

 

well i found a kit that i want but im not sure how much HP it will produce and if it will fit the klx motor please help me out with this. heres a link to the kit.and does it mean that the cyclinder come with the kit?



YX 4 Valve Race Head and 62mm Bore Kit

I have done a cam mod that brings this kit to life.

One of my sons has had this kit on his bike over a year without issue.

 

I have done a cam mod that brings this kit to life.

One of my sons has had this kit on his bike over a year without issue.

so which one would be better?

 

for your application , since you have the 55 crank, I think you would be happy with the TB setup as the 4 v needs a Honda style intake and a pipe adaptor.

 

for your application , since you have the 55 crank, I think you would be happy with the TB setup as the 4 v needs a Honda style intake and a pipe adaptor.

well could i use the tb v2 head and a 178cc cyclinder and piston for more power?

 

well could i use the tb v2 head and a 178cc cyclinder and piston for more power?

oh yeah,,

 

oh yeah,,

do you know where to get that cylinder at? and so would that make it a 190cc with the 55mm stroker crank?

 

will the scut one work?

 

yes that will work if you talkin about the tak. 178 piston and cylinder and the tb v2 head. Thats what i was running on my bike with the stock crank and it was pretty much a beast, ran great, before it got stolen. You will need a 28mm carb tho, if you dont have one. If your running the stroker crank you have to be careful with valve clearence if your running a big cam like the s-35 but stock crank will clear fine. If you want to go with a 160 kit i have one for sale kitaco se big valve head with bbr race team mods and bbr decomp cam, bbr 160 piston and cylinder, and the intake manifold that matchs the se intake port. decomp cam is sweet i can start the bike with my hand. Its still on the bike and runs great. 500$ check my other posts i have pictures of everything

 

and also if your going with that big of a kit you should get the heavy duty cylinder studs so the dont stretch and losen up

 

going with the v2 kit is a better bang for your buck. the yx 4 valve has potential but it requires a good deal of work to get it. the stock valve train in the yx is terrible i have seen two kits and both kits the rockers hit the retainers before the shim. at 160cc 28mill carb and decent exhaust expect to see around 12 ponies.

this shows some of different port jobs i did with stock valve train



with big ti valves porting welding and rechambering the combustion chamber i got 18.5

 

What are all those squiggly lines supposed to mean? Don't go confusing people with real facts...

All that matters is how it does in a dirt drag... lol

We've run them on pavement tracks, plenty, and the 4V gets smoked, as the graphs indicate they should.



But, as I'm sure many will attest, a good rider can open enough Dr. Guff's to get around on about any thing...





Nice work, Chad! Final configuration made some respectable, printable numbers. The wide peak shows quality porting and the real 4v advantage. Early sign off can be geared around, and save the lower end some grief. Thanks for the spare valve! My ported 4V with shortened regular 2v YX160 cam should be fine for the CL for cruising the 'hood. Honda port means I don't have to make a pipe, and can still run the air filter inside the frame for noise reduction. With some stiffer valve springs and the smaller displacement, it might be fun on your XR/KLX hybrid. Make some Lexan valve covers, for the REAL 4V advantage to become clear



BTW, the initial numbers weren't with the as-shipped .015-.018 lash yours had, were they? Mine had ZERO intake, .017 exhaust, out of the box.

 

will the scut one work?

You could run the scut, I personally only like the full skirt setups , more suface area for heat dissipation, lubrication , and strength.

My opinions are based on actual usage , I have not only built dozens of TB equipt engines, but 5 custom modded versions of the YX 4v, and have actually ridden and raced them all many times on short tracks as well as big bike tracks as you have asked in your title.

You will get responses from a few that might have actual seat time with these setups and really do race these things and many that have none or limited actual time with them .

I suggest the TB fullskirt as the easiest bolt on and reliability, but the YX 4v with some work can be as competitive and reliable.

 

You could run the scut, I personally only like the full skirt setups , more suface area for heat dissipation, lubrication , and strength.

My opinions are based on actual usage , I have not only built dozens of TB equipt engines, but 5 custom modded versions of the YX 4v, and have actually ridden and raced them all many times on short tracks as well as big bike tracks as you have asked in your title.

You will get responses from a few that might have actual seat time with these setups and really do race these things and many that have none or limited actual time with them .

I suggest the TB fullskirt as the easiest bolt on and reliability, but the YX 4v with some work can be as competitive and reliable.

some work? kinda of a understatement dont you think? combustion chamber needs worked which lowers your cr more on a fairly low cr setup. so your choices from there are deck which your going to then have to slot cam and degree back or source a piston. if you use the 150r piston on the klx or yx160 you will have to change rods or work the rod you have to match the bigger wrist pin. valve job and seats are chit at best. both kits i had in my hands the rocker arms would hit the retainer before the shim and a few other guys that have the kit ran into the same problem so chances are most of them are like that if not all. so you will have to work the rocker arms so they contact the shim and not the retainer. most of that the average joe builder wont be able to do so then they will have to pay someone else to do so. dont get me wrong i like my head but its not a tweak here and everything is sound realiable.

 

some work? kinda of a understatement dont you think? combustion chamber needs worked which lowers your cr more on a fairly low cr setup. so your choices from there are deck which your going to then have to slot cam and degree back or source a piston. if you use the 150r piston on the klx or yx160 you will have to change rods or work the rod you have to match the bigger wrist pin. valve job and seats are chit at best. both kits i had in my hands the rocker arms would hit the retainer before the shim and a few other guys that have the kit ran into the same problem so chances are most of them are like that if not all. so you will have to work the rocker arms so they contact the shim and not the retainer. most of that the average joe builder wont be able to do so then they will have to pay someone else to do so. dont get me wrong i like my head but its not a tweak here and everything is sound realiable.

While I admire the effort and work put into your YX 4v head as well as the results you were able to get. There have already been hundreds of the YX 4 valve engines produced and as you can see PM is not littered with horror stories of head failures.

I only have few engines running the crf150 piston, the rest are still running the YX 62mm piston , not major head rework , just some simple improvements and they now rip!



I still say for this guys application, the TB v2 and 64mm would be ideal.

 

Just cause planetminis is not filled with it does not mean its not going on. I have talked to a few that has already had failures and I'm a no body. I do agree the tb is the best kit for this gentlemens needs.

 

ur guna need moew cash than that....get a race head

 

ur guna need moew cash than that....get a race head

Littering and... Littering and... Littering and...