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hello guys i had just recently baught a trx450r and i was checking my valves to see if they were in spec on the stock cam it is an 05 and looks too be in good shape well i got everything the way its suppose to be at tdc and on the intake i cant get a feeler guage in either left or right they are tight with no clearence i got a .007 guage in but had to force it in and pry to get it back out very tight anything lower would just bow well i did mic my shims left was .068 and right was .069 do i need to start at zero or do i go by the .007 which i had to force to get in and if so how do i get my calculation. i also baught a stg 1 hotcam for it and been wanting to try it out i did install it but same thing cant get a clearance on the intakes again too tight i did take it back out and put the stock cam back in did not want to screw up anything so untill i can get some help im not going to ride it but my bike does start up first or second kick all the time and has good compression and runs out good it has stg 2 jet kit a hmf slip on and uni aftmrket filter everything else is stock so where would u guys start at do i just start at zero because there is no clearence at all very tight no gap sorry for the long thread just trying to get everyone on what im dealing with and how to fix it thanks
 

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Sounds like you have some wear on the valves and seats, need to get a hotcam shim kit so you have an assortment to choose from not sure about the clearancd on the 05 but mine are set a .006 int and .011 ex not sure how thick of a shim you will need but their is a limit to how thick of a shim you can use if you are past that limit you will need a valve job
 
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Discussion Starter · #4 ·
thanks for the info guys might as well get some new valves and be done with it so i know what i have maybe a shim kit too which is good to have if u own a 4 stroke
 

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yes a shim kit and a set of micromaters is a must have
 
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hello guys i had just recently baught a trx450r and i was checking my valves to see if they were in spec on the stock cam it is an 05 and looks too be in good shape well i got everything the way its suppose to be at tdc and on the intake i cant get a feeler guage in either left or right they are tight with no clearence i got a .007 guage in but had to force it in and pry to get it back out very tight anything lower would just bow well i did mic my shims left was .068 and right was .069 do i need to start at zero or do i go by the .007 which i had to force to get in and if so how do i get my calculation. i also baught a stg 1 hotcam for it and been wanting to try it out i did install it but same thing cant get a clearance on the intakes again too tight i did take it back out and put the stock cam back in did not want to screw up anything so untill i can get some help im not going to ride it but my bike does start up first or second kick all the time and has good compression and runs out good it has stg 2 jet kit a hmf slip on and uni aftmrket filter everything else is stock so where would u guys start at do i just start at zero because there is no clearence at all very tight no gap sorry for the long thread just trying to get everyone on what im dealing with and how to fix it thanks
from the looks of your numbers, you should start with 0.062(to replace the 0.068) and a 0.063(to replace 0.069). these shims will be 0.006 smaller, your required intake clearance. this will prob not be bang on but it should get you close enough to calculate what size you need.

69quadracer is correct on valve clearances
set you decompression to an additional 0.006 on top of your 0.011 exhaust clearance

you may want to replace the air filter because the 04/05 models have all steel valves that don't wear as bad as the new models. normally they are a very dependable valve train in your model, makes me think there must be a reason for the seats wearing(dirt making it into your engine)
 

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Get a service manual and follow the instructions. You can learn by the mistakes you made.
why don't you tell us what mistakes he made!
i tired of your a$$hole remarks to people. i see that you do help some people but if you don't know the answer then you turn into a A$$.

if you don't have anything useful to say or are in a bad mood, stfu! people don't need you to tell them to "take it somewhere and have it fixed right". they will figure that out on there own if none of the nice guys on here help them out
 

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Get a service manual and follow the instructions. You can learn by the mistakes you made.
why don't you tell us what mistakes he made!
i tired of your a$$hole remarks to people. i see that you do help some people but if you don't know the answer then you turn into a A$$.

if you don't have anything useful to say or are in a bad mood, stfu! people don't need you to tell them to "take it somewhere and have it fixed right". they will figure that out on there own if none of the nice guys on here help them out
OK. Since I cannot quote the service manual, you will have to bear with me if my explanation is not fluid.
Now it makes no difference if you are using the stock cam or an aftermarket cam. In therory, all the cams have the same base circle for the engine they are designed to be used in. The maximum thickness of a shim is of no concern. The minimum thichness of a shim is critical. When you reach the mininum thickness shim, you have to replace the valve.
Since no feeler gage can be inserted (without force) you have to presume the clearence is zero or less. (less meaning the valve is actually open a thousandths or two or more) Since the shims are measured in millimeters it is redundant to measure the shims in thousandths. Each shim is marked with it's thickness to one one-hundredth of a millimeter. You should measure the clearence in milimeters.
Since a little extra clearence is more desireable than too little clearence, you should calculate the desired shim thickness by checking the thickness of the installed shim and subtracting the desired clearence (or in this case, the specified clearence).
Compared to the valve seat, the valve is soft. As the valve face erodes, the clearence between the cam and valve lifter decreases. Running "high flow" air filters will speed the erosion by allowing a greater amount and larger particles of dirt to enter the engine. The intake valves usually wear faster than the exhaust valves because the exhaust valves are harder (to resist the heat) and the intake valves are closing on dirty air.
Each time the shim is changed it is prudent to rotate the engine to open and close the valves to "seat" the valve and make the clearence measurement more accurate.
I race a Honda. When I adjust my valves, I set the clearence to the loose side increasing the length of time between adjustments and reducing the possibility of the valve clearence "zeroing" out while riding before the next service interval. These are "race bred" engines. The valves need to be checked regularly and frequently. The piston and rings need to be replaced at the specified interval to prevent engine damage. Don't whine about a dime. You purchased a high performance vehicle and high maintenance cost are incidental.
So, there you are. I spent an hour typing this explanation (with few or no mispellings and gammatical errors) while I could have physically performed the service in less time. Now you can attempt to service your own engine and with luck, not damage anything beyond repair. While you are working on yours' I will be riding mine.
 

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Discussion Starter · #9 ·
man i do appreciate ur time and everyone is so helpfull thats why i am in this forum u guys are so helpfull like i said i can do some things but u can learn alot more by talking to others just rather be safe than srry.
 

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well i checked my shim kit,
your 0.068 is actually 0.0679=1.725mm
dropping your 0.006 for clearance puts you at 0.062=1.575mm

your 0.069 is actually 0.0689=1.75mm
dropping your 0.006 puts you at 0.063=1.6mm

these #s will only be correct if your valves were not being held open at all(chances are slim)

you still have some life in your head, you can go down to a 0.0472=1.2mm. that is 15 shim sizes smaller then the 0.062 you need to install(and recheck)

you will prob end up needing between a 0.062=1.575mm and a 0.060=1.525mm ind the end

i hope this helps you, don't be intimidated its not too hard. july dirtwheels has a article on how to do it with pics if you think that would help you. oh and i hope you have fun riding heretohelp:p
 

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Yeah whatever - my shims come in thicknesses of 1.45, 1.50, 1.55, 1.60 etc. Good luck finding 1.575 and 1.525 thickness, or should you round off? Then 1.575 becomes 1.60 or maybe 1.55 and 1.525 would be 1.50 or maybe 1.55. Which should you choose, the 1.60, 1.55 or the 1.50? It's eaiser to measure in millimeters and calculate in millimeters.

If you think it's not likely the valves might have zero clearence or less, then you haven't worked on many of these motors. Especially ones that are raced and not maintained at regular intervals.

I noticed that the service manual has a nice article with pics that will really help and it covers other maintenance chores also.

joey, what adversion do you have against service manuals? have fun working on your motor.
 

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Discussion Starter · #12 ·
thanks joey u are very helpfull unlike other ppl who try to be and has a rude way of showing it and this is the first ever trx that i have owned so i really dont know much about them i like to try to do stuff myself so the shops dont rip me off and untelling what else they would try/will do to it they are rip offs but thanks to everyone who has been apart of this thread
 

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q1 Yeah whatever - my shims come in thicknesses of 1.45, 1.50, 1.55, 1.60 etc. Good luck finding 1.575 and 1.525 thickness, or should you round off? Then 1.575 becomes 1.60 or maybe 1.55 and 1.525 would be 1.50 or maybe 1.55. Which should you choose, the 1.60, 1.55 or the 1.50? It's eaiser to measure in millimeters and calculate in millimeters.

a1 after your last "helpful" post you explained that he should round it down, right smarta$$
hondamans post was in standard not metric so i said what would make sence to someone new to 450s

q2 If you think it's not likely the valves might have zero clearence or less, then you haven't worked on many of these motors. Especially ones that are raced and not maintained at regular intervals.

a2 i said that it was unlikely that they were at 0, prob less if you read it properly

I noticed that the service manual has a nice article with pics that will really help and it covers other maintenance chores also.

q3 joey, what adversion do you have against service manuals? have fun working on your motor.
a3 actually i do enjoy working on Rs, you are just upset that i called you out:p and i have manuals for both models, i just figured he could buy dirtwheels and have some reading material after the work is done
 

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ok u wen. i bin dooin it rong 4 the last 40 yeerz
i didn't think it was a contest to "wen", but since you always have a remark,

1.575mm shim is part# 14916-MBB-000

1.525mm shim is part# 14914-MBB-000

these part# are from honda, not hot cams, hth
i use a hot cam set, but there are other options

did you need me to mail them to you? since you have a hard time finding them.

i didn't say you were doing it wrong, i just said you are an a$$ to people that come on here to save money and always have stupid remarks, i would have thought you would be more respectful after 40 yeerz

i hope you keep helping people
 

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Sorry I didn't get to respond earlier - I was too busy at the time to reply, but I did get to scan the site.

Of course you are right about the "in between shim sizes", but why would I (or anyone else) want to buy a $7.00 shim from Honda when I can buy shims from a supplier like K&L Supply for $3.00? I don't see that valve adjustments need to be made in 1 thousandths of a inch increments when the average shade tree mechanic can't "feel" the difference between 1 and 2 thousandths of an inch and Honda recommends an allowance of plus or minus 1 thousandths, so it's a moot point

My engine has a specified valve clearence of .12mm intake +-.03 = (.005 +-.001 inch) and .28mm exhaust +-.03 = .011 (+ or - 1 inch) exhaust. I just use a (in mm) .15 and .09 feeler gages. If the .09 goes and the .12 does not, I'm done. If I need to change shims then I just use shims in .05mm increments at $3 each instead of .25 increments at $7 each. It's just simple economics.

I work on all brands of motors. I have about $1000 in shims on hand. I can't justify doubling that investment for .001 of an inch accuracy when that accuracy is not required.
 

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Yeah whatever - my shims come in thicknesses of 1.45, 1.50, 1.55, 1.60 etc. Good luck finding 1.575 and 1.525 thickness, or should you round off? Then 1.575 becomes 1.60 or maybe 1.55 and 1.525 would be 1.50 or maybe 1.55. Which should you choose, the 1.60, 1.55 or the 1.50? It's eaiser to measure in millimeters and calculate in millimeters.



Sorry I didn't get to respond earlier - I was too busy at the time to reply, but I did get to scan the site.

Of course you are right about the "in between shim sizes", but why would I (or anyone else) want to buy a $7.00 shim from Honda when I can buy shims from a supplier like K&L Supply for $3.00? I don't see that valve adjustments need to be made in 1 thousandths of a inch increments when the average shade tree mechanic can't "feel" the difference between 1 and 2 thousandths of an inch and Honda recommends an allowance of plus or minus 1 thousandths, so it's a moot point


I didn't quote it, but if read correctly it says that i use the hot cam kit. $$
 
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