185s head porting, worth it?

[tbirdscott]

As the title says I have a 1981 185s atc and I'm doing the top end at the moment and was wondering if theres anything that could be done to the head that would benefit it. I searched but couldnt find any info on this.

Thanks
Scott

[team-red-rider]

talk to Ronnie...aka Yamahondaman here on the forums ...hes an expert on this

[RedRider_AK]

LOL Head porting and polishing on a 185 sounds like adding a supercharger to your LT80. It'll add some power and speed, but you're still gonna be going slower than sport machines.

Joking aside, if it's not too expensive and your motor is in good mechanical shape, I'd go for it. Polish up those intake and exhaust tunnels (whatever they're called on a 4-stroke) and widen em up a little, give it more room to breathe. After that, you might wanna find a 200X frame to stick the engine in, because you'll be disappointed with the stock frame.

[SYKO]

yea it can never hurt doing mods to what you got, even if its a 185, it could be made out to ba a badass 185!

[RedRider_AK]

Do the head porting, slap a hi-comp Wiseco in it, a Web or Powroll cam, stick the whole thing in a 200X chassis with Mudlite SP's and you have the ultimate trail ragger.

[tbirdscott]

I've got a couple 200's that I will be picking up in the next couple weeks so there wont be any frame swaps or anything on this guy, just a good little beater bike. I'm in northern British Columbia so top speed isnt an issue, it was already more than fast enough for cruising the trails with a 3/16" ring gap (how it still ran I dunno :wondering ) just needs more tire under it to get through the quad ruts.

The reason I asked is 'cause it'll be another week or so till my rings are in and i've got the tools and time to do it, i'll probabally at least polish the ports. Finished stripping the frame today and will get it painted tonight or tomorrow, my cheap toy project is snowballing :rolleyes:

Thanks guys

Scott

[RedRider_AK]

If you're just going for a trail/mud rider this will be a good mod to do as well, it'll give your little 185 engine a little more balls to spin the bigger tires you want.

[BarneyNZ]

check out this site

http://www.freewebs.com/trikerbuildoff/index.htm

[KASEY]

I've got a couple 200's that I will be picking up in the next couple weeks so there wont be any frame swaps or anything on this guy, just a good little beater bike. I'm in northern British Columbia so top speed isnt an issue, it was already more than fast enough for cruising the trails with a 3/16" ring gap (how it still ran I dunno :wondering ) just needs more tire under it to get through the quad ruts.

The reason I asked is 'cause it'll be another week or so till my rings are in and i've got the tools and time to do it, i'll probabally at least polish the ports. Finished stripping the frame today and will get it painted tonight or tomorrow, my cheap toy project is snowballing :rolleyes:

Thanks guys

Scott
if your going to do the porting yourself,,, i say leave it alone,, just shining the ports will do nothing, there are other bottle necks in a 185,, the exahust, the carb,, the ports will flow more than either of these will ,,, just re=ring it and be happy,,,

[tbirdscott]

Holy old thread batman!

I did a little work to the head but not much. I added a larger carb (2mm larger I think, it was a while ago) and made my own muffler since the original was long gone when I got it. Put on a set of trail pros (I love them) and the little bugger just screams.

I'm building up another engine right now. 1983 200s bottom end, I have a 'Hi-Performance' camshaft (still need to measure a stock cam to see how it compares) and another head to grind away at. I've got a 185 cylinder I'm going to bore out to 200 and put in a wiseco high compression piston I havnt decided on a ratio yet. I'll probably pick up a small supertrapp silencer and bend up my own head pipe for it. Then I'll need to build something to put it into :naughty: havnt gotten that far along yet.


Scott

[81Rmachine]

If your going to port just remember that it's all about port velocity. If you still want good low end which Hondas have alot of you dont want to hog it out. Unless your putting in a bigger cam the port job depending on how you do it will make barely any difference or can make it worse. My brother had his 200x head hogged out because he had planned running a bigger cam. Well he still hasn't gotten a cam yet so as of now he has actually lost some power which is definately noticeable when you race a friend who you were neck and neck with and you all the sudden get your ass handed to you. Once he gets a cam he will sure notice it though.

[Erics350x]

Save your money for an X or R