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  #61  
Old 11-12-2009, 10:02 PM
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(copied from NR RACING WEBSITE... SORRY)

Valve, Intake, Stainless, 25 mm Stock Size & Length, Lightweight, High Flow, Hardend tips (Lash caps not required)








VAL25-000 $16.00
Valve, Exhaust, Stainless, Stock Size & Length, 24 mm, Lightweight, High Flow, Hardend tips (Lash caps not required)




so... looks like SOME stainless valves dont require them..

Tyler WE BOTH ARE RIGHT
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  #62  
Old 11-13-2009, 09:24 AM
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Ok, If you like your rocker arm getting stabbed by a 7 mm valve stem with 35 lb dual springs then don't run lash caps lol. Personally I would always run lash caps.
  #63  
Old 11-13-2009, 09:37 AM
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hes NOT running 35lb springs man.. 18lbers is what he has
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  #64  
Old 11-13-2009, 09:56 AM
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I know, Just saying. Even with 18 pound springs I would still run lash caps.
  #65  
Old 11-13-2009, 02:26 PM
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i'll run the lash caps. i think it's a good tip. but will the cam pull hard all the way through the power band?
  #66  
Old 12-01-2009, 08:50 PM
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have you bought these parts yet? i read somewhere that using the 1.3:1 rockers will make the stock cam have a near .290 lift. i know, i read the dissertation on what matters more on a cam. from what i have seen on jap and these small engines, some of the best gains are from a mere carb swap. what of shorter pushrods/lifters? will they not be a multiplier for lift? i have also read that a gx200 flywheel/rotor used on a gx160 will give you 20* of advanced timing. i thought it a bit much if you aren't running a really hot engine. they also threw in a 8* key in the kit. does anyone make needle bearings for the cam? getting torque is probably easiest from the stand point of spacing the carb. get the two piece adaptor, and use a length of radiator or similar hose between the carb and head. depending on how much torq you intend on having will dictate how much hose you will have. i would buy two hoses, one to experiment with, one for fine tuning. the bugle pipes are supposed to give good gains as well. just rememeber, if you want the powerband a certain way, you have to tune that way. where is a needle in a 390 carb? it is not the same one as in a mik or kiehn. honda's odyssey had a 'T' that acted as a pressure regulator on their t/s 250. i think it is $20. gravity flow should be fine as most miks and kiehns are for gravity applications. ie motorcycles, atvs etc. in dealing with the bigger engines, blow by becomes an issue. this is only posed as a question for those who know more than i. if you were to remove the 'reed valve' in the rocker cover, would it not ease the blow-by situation? a cotton or metal mesh as in car breathers would catch the oil and return it to the crankcase. these engines would be so much easier to do if the cylinder was removable from the block!! as to fuel pumps, i've been told napa sells an electric one for $12-16. i'm thinking.... yep, that's about it for cheap and easy. if upgrading the carb, i would definitely go with mik or other slide type carb. they are way more adjustable. oh and a hotter plug depending on compression and timing. that's it, i out!
  #67  
Old 12-01-2009, 10:46 PM
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Quote:
what of shorter pushrods/lifters? will they not be a multiplier for lift?
If you just think about it for a bit, you'll see why they don't give more lift
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  #68  
Old 12-02-2009, 09:26 AM
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depending on how long the stock ones are, shortening them a bit could allow for more deflection, or greater lift
  #69  
Old 12-02-2009, 11:05 AM
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how in the world do U think a SHORTER pushrod.. will give MORE lift c'mon man

also The GX160 has 5 degrees more advance into the FACTORY flywheel so if you install a Gx200 flywheel on a 160 you just RETARDED the timing 5 degrees. and an electric fule pump is OVERKILL you can isntall a pulse fitting and get the job done with a pulse style pump..
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  #70  
Old 12-02-2009, 07:07 PM
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by having a shorter push rod, it will throw more capacity to opening the valve. just as having too long of one will make it so the valve doesn't open as much. ever used bell cranks or other cantilevered items? sure you have, there are extra holes for you to attach your throttle cable on the honda/clone throttle arm. if you put it in one hole, it does not have to pull as far, but it does increase the amount of torque required to turn it. if you put in in the hole further away, it pulls more cable with less stress. has honda really done all the homework on this? most likely not. they mildly if any kind of tune these engines. i have read otherwise on the flys/rotors. course, it could be a gimmick to buy parts. i don't have a genuine gx200 to compare flys. as to the fuel pump, the electric is cheaper, and being of automotive grade, should last longer. it could be said that supping these engines up to 20hp or more is overkill as well. not to mention how much it costs. FYI, honda says the 160 produces 4.8hp@3600; the 200, 5.5hp@3600. looks like we are getting gyped (from gypsy)
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Old 12-02-2009, 08:33 PM
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yeah those numbers are correct. honda posts the power curves on their website. Noticed that the other day... http://www.honda-engines.com/engines/gx160.htm
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Old 12-03-2009, 02:51 AM
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Quote:
by having a shorter push rod, it will throw more capacity to opening the valve. just as having too long of one will make it so the valve doesn't open as much. ever used bell cranks or other cantilevered items? sure you have, there are extra holes for you to attach your throttle cable on the honda/clone throttle arm. if you put it in one hole, it does not have to pull as far, but it does increase the amount of torque required to turn it. if you put in in the hole further away, it pulls more cable with less stress
This has exactly NOTHING to do with the length of the pushrod. You seem to be confusing pushrod with rocker arm.
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  #73  
Old 12-03-2009, 05:52 PM
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no, i realize the geometry involved, and if the pushrod is too short or too long you lose capacity for opening. the rocker's bias should be to the pushrod. just barely to the p/r. if to much bias one way or the other, it will hinder the translation of lift to the valve. by optimizing p/r length for a given set of lifters, rockers and valves, you may be able to get some extra lift.
  #74  
Old 12-03-2009, 06:38 PM
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If the pushrod is too long the valve will not shut, and the engine will probably not run.
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  #75  
Old 12-03-2009, 06:47 PM
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the p/r should never be allowed to not close the valve. depending on length, the rocker would jam against the pivot and not fully open the valve. too short, and it won't open fully either.
  #76  
Old 12-03-2009, 08:51 PM
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talking about pushrods are the stock pushrods ok for 9.5 to 1 compression ratio?
  #77  
Old 12-03-2009, 09:47 PM
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i'm just uping the compression with a flat top and and putting in a cam and some spring. everything else is just insurance that my engine won't blow up. how hard is it to put in 26 lb springs?
  #78  
Old 12-03-2009, 10:17 PM
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are you gonna go with the 1.2/3:1 rockers? if i am not mistaken, they can be found on the gx340/390s. i had a 340 that i swiped the rockers from (bare block, except cam, complete head) they are longer, by approx. 1/8".
  #79  
Old 12-04-2009, 10:35 AM
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if have 1.2 rockers
  #80  
Old 12-04-2009, 08:55 PM
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http://cgi.ebay.com/ebaymotors/GO-KA...Q5fCarQ5fParts
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