Quantcast
Jump to content


lt230s increased compression question...


berryjo5

Recommended Posts

hey guys, i just recently installed a wiseco piston that increases my compression from stock which is 9.0:1 to 10.5:1. I am wondering if i have to do any jetting work in the carb, if i should run any different plugs (colder or hotter than stock), what octane fuel you would recommend (im thinking 91 or higher), and also what would be the best way for breaking everything in...

im thinking some extra information might be useful before i fire this thing up :biggrin:

thanks for the help guys!

Link to comment
Share on other sites

whats up mike! havent been on in awhile, been pretty busy lately lol... see i wasnt sure if i had to rejet because theoretically i am not adding any more fuel or air, i am just compressing the same amount alot more which made me think that maybe i dont need to rejet. Ill prolly throw some sunoco 94 octane in it today. the higher the octane the more resistant to detonation it is so i figured 94 is a safe start and i can always work my way down to say 93 or 91 octane.... any suggestions on what plugs to run or break in?:wink:

Link to comment
Share on other sites

You should be fine on premium pump gas, just use good gas. I imagine that motor would be good on pump gas up to about 11.5:1 or so. Depending on how the engine is built, more modern motors can run up around 13:1 before you really need high octane fuel, that is pretty much the limit though, many people run race gas or a mix of race and pump gas at that point.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Similar Forum Topics

    • By ResQ91
      Hi Guys!

      New member and could really use your advice. I would have to believe this has been an issue for others but a search here came up with nothing......? (Probably me not doing search correctly)
       
      I have an 87 Big Bear 350 YFM350FWT
      The OEM Mikuni BTM carb is shot and would rather replace than rebuild.
      It is no longer made and I have had good luck with NICHE carbs so I ordered a #K-CRB-0006 This was what they said was replacement when ordered. This Carb only uses 1 Throttle cable. The Slide is linked so it uses one. (OEM had 2nd cable coming through top to move slide)
       
      Problem is when I ordered a replacement Cable from NICHE (#C-CBL-0061) the Cable wire is a little short, not allowing Throttle to return all the way down to Idle position. I called NICHE and they are at a loss. Haven't gotten back to me after 2+ weeks.
       
      What would you recommend other than a carb rebuild?
      Can I just use 1 of the OEM cables (It is the right length) and snip/disconnect the other that went to top of Carb for Slide?
      Or ??
       
      Thanks in advance for any advice you have!!
       
      Dave
    • By Drillbit
      Hey all,
      I need some input on a problem I'm having with my Kodiak 400 that keeps fouling plugs. First off, I've done a lot of work to this thing, most of it all in good fun. Brake work, cv joints, u joints, carb kit, checked valve lash, compression good, changed all fluids, etc... My problem is it keeps fouling plugs very quickly. I can put a new (manual recommended plug) in and it starts right up, runs great, idles great, picks up good. Doesn't stutter at all. I ride it for 1/2 a mile, it cuts off and won't start back up. I let it sit overnight thinking maybe it got to hot. Try to start it the next day, nothing. Put a new plug in, fires right up, runs great for another 1/2 mile or so, dead. The plugs come out and look carbon fouled with dry black soot on them. I don't know if this is a fuel/air mixture problem or a ignition problem. A couple of things that I noticed is I never need to pull the choke out to start it. Also, when it starts it automatically idles high like an automatic choke would do, then it comes back down to a good idle. Also I noticed that the air/fuel mixture needle valve screw does nothing when I adjust it in or out. I can screw it all the way closed and the motor still runs and idles good. Any advice would be greatly appreciated. I'm almost leaning to a ignition breaking down the plugs??
      Thanks! 
    • By DarkRider
      This is something I'm extremely curious about. Has anyone ever attempted to buy a quad (or any other vehicle) from an impound lot? I've always wondered if this could be a bargain, or a waste of time. Google searches do turn up some helpful results. Looks like the state of NJ holds auctions online which I'd be a bit hesitant about.
       
      My online searches haven't really turned up any results of anyone buying an ATV this way. I'd be really curious if anyone tried this, or knows someone who has. I've actually found a couple pages with online auctions for my state, but none had ATVs.
    • By jashadams
      Hey all back again with my 1989 moto 4 250.
      After putting a new carb on it it's really sputtery, it has new gas and I'm wondering what to tune on the carb to make it idle better. I've attached a video to describe the issue more. The bike is still work in progress but I think the video gets the point across. Thanks!
      Snapchat-1142015191.mp4
    • By p5200
      Hello folks, my machine wound up with I think water in the tank etc. It runs but speeds up and slows back down randomly. When not running I don't see gas dripping  from the drain nipple on bottom of float bowl and drain screw is closed tight. With normal idle speed I see no leaking. When the idle speed increases quite a bit on it's own, gas appears to start slowly dripping from float bowl drain nipple? I'm wondering if the carb is flooding and the gas is actually coming from higher up and just appears, to be coming out of nipple but, is actually running down the sides of the nipple? I put a kit in the factory Mikuni carb last year after sitting for a while and I think the gas in the jug I used had drawn moisture. I plan to pull the carb tomorrow and clean everything out. I was just curious if anyone else thinks it's probably something in the carb and is, acutally a flooding problem? Thanks Folks! 🙂
×
×
  • Create New...