Reaming new valve guides?


11 replies to this topic
  • ndekens

Posted September 21, 2006 - 08:14 AM

#1

When installing new valve guides and new valves do you have to ream the new guides? Just wondering because the valve guide section of my service manual says install the new guides and ream them........okay but why and what diameter do you ream the new guides to? Wouldnt new guides and new valves be already matched to the correct sizes?

  • kelstr

Posted September 21, 2006 - 02:14 PM

#2

When installing new valve guides and new valves do you have to ream the new guides? Just wondering because the valve guide section of my service manual says install the new guides and ream them........okay but why and what diameter do you ream the new guides to? Wouldnt new guides and new valves be already matched to the correct sizes?

well with the really good cv4 tight valve guides, when they get installed they are alittle snug,--( but then again i like the guides snug ) -----the honda and yamaha factory guides are already loose anyway ----
i have never had to ream a factory guide ( except chevy, dodge and ford crap)-----now some times when you are installing them if you step on your dick and get is a hurry and you do not get the head hot enough and you have to hit the guide hard to install it you can kinda deform it and swedge it tight in some spots,------so yes there is a set of reamers that run from 2.5 mm up to 3/4"
but the yamaha guides are kinda ok----but the honda guides are loose anyway.

but when i get the nice cv4 guides installed and the valve will almost not go in the guide , i will use a .195-.196 ( thats like 4.96 4.97mm ) reamer to loosen it up alittle to get it where it just goes in and thats all .

you can also take one of your old valves and cut the head off and put the stem in your drill and work that old stem and some polish or rubbing compound and polish her out to where it fits free and nice but with little or no play .

but yes there is a reamer set , mine is an automotive set that i paid way to much money for that has several hundred nice reamers for just about any hole you would want to ream, ( king pins , out drives , trans bushings, aileron bushings :lame: )
they are cool to have but for this purpose unless you really step on your dick you wont need them -------i believe FLANDERS, GOODSON , E.T.W and or KENT MORE all now have nice little motorcycle sets that have like 4.0,4.02, 4.80, 4.9, 5.0, 5.02, 5.5,5.8 , 6.0 , 6.5 , 7.0 ,8.0. ----the normal twelve that a motorcycle guy would use in his travels :p
also FLANDERS, and GOODSON will sell just one reamer if you needed it--a 4.95 mm or a .195 IN reamer would do you on a 250 , ----the bigger intake valves of the 450 would take another 5.47 mm or .215 IN reamer for those :thumbsup:

  • Ron Hamp

Posted September 21, 2006 - 03:05 PM

#3

the stock replacement honda guides are well undersized and have to be reamed first the cv products guides are close and only requir honing i have a small sunnen guide hone that cost way to much but i prefer to hone my guides to size and use a guage pin for fitment.

  • kelstr

Posted September 22, 2006 - 04:01 AM

#4

the stock replacement honda guides are well undersized and have to be reamed first the cv products guides are close and only requir honing i have a small sunnen guide hone that cost way to much but i prefer to hone my guides to size and use a guage pin for fitment.


boy the first set of exhaust guides i got from honda for an 02 450 were looser than i liked ,
i was disappointed :bonk: ----so i have not bought honda guides again :thumbsup:

i just really like the CV4 guides ---there stuff is really good :p .

hey Ron i have the little sunnen rod resizer hone for repairing rod ends that i can hone guides in also , the tool has the heads and collets running horizontal ----which it kinda ok,--not really what i would prefer :lame:

i wanted to get that little guide hone you have but i could never find a used one that was not beat all to Hell and had all the tooling ruined :eek:

is yours the one that sits on the bench or is yours the one that sits all by itself and has the bench and cabinet all in one ?

  • Ron Hamp

Posted September 22, 2006 - 05:00 AM

#5

Kelly its stand alone and goes in a drill motor there in the back of the goodson book.

  • crowerpowerhp

Posted September 22, 2006 - 05:47 AM

#6

we have our own phosphur bronze guides , they go in perfect with no distortion and no honing or reaming needed 11 $ ea....we had some made spl. so we can avoid all that above nonsense in honing and reaming.....takes 15 min to reguide a honda ...cost is 70$ parts and labor and recut exh. seats is included......the intakes are always good , no side load going on there , the exh guides are another story , side stem loads are way up over there.

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  • crowerpowerhp

Posted September 22, 2006 - 05:50 AM

#7

send the cam in also with the head and we do the G1 race grind with new intake springs for 219$

  • kelstr

Posted September 22, 2006 - 07:35 AM

#8

Kelly its stand alone and goes in a drill motor there in the back of the goodson book.

oh that one ----yes he is a cute one ---but he aint cheep :thumbsup:

  • kelstr

Posted September 22, 2006 - 07:41 AM

#9

we have our own phosphur bronze guides , they go in perfect with no distortion and no honing or reaming needed 11 $ ea....we had some made spl. so we can avoid all that above nonsense in honing and reaming.....takes 15 min to reguide a honda ...cost is 70$ parts and labor and recut exh. seats is included......the intakes are always good , no side load going on there , the exh guides are another story , side stem loads are way up over there.

Dan ---are your guide nice and snug with no play when done ?

that is the one thing i just hate is when you get em installed and they still have movement and play in them .

i almost feel cheated if i did not have to fit the guide alittle so i could set the clearance ,
but then again i am queer like that on stuff and like the final fittment snug on stuff almost to a fault :lame: :p :thumbsup:

  • Bodyman

Posted September 22, 2006 - 08:23 AM

#10

we have our own phosphur bronze guides , they go in perfect with no distortion and no honing or reaming needed 11 $ ea....we had some made spl. so we can avoid all that above nonsense in honing and reaming.....takes 15 min to reguide a honda ...cost is 70$ parts and labor and recut exh. seats is included......the intakes are always good , no side load going on there , the exh guides are another story , side stem loads are way up over there.


those guides sound interesting but I have a question on not cutting the intake seats.... Any used seats need a dress up 90% of the time...

  • Throttlejockey

Posted September 22, 2006 - 11:28 AM

#11

.... Any used seats need a dress up 90% of the time...



No kidding. After 10 hrs they're already hammered.

  • kelstr

Posted September 22, 2006 - 12:58 PM

#12

those guides sound interesting but I have a question on not cutting the intake seats.... Any used seats need a dress up 90% of the time...

oh god yes, ---you and Fred are so correct.
to do the job you must cut all the seats ,-----these motors really do put a pounding on the seats ------putting a fresh valve in an uncut seat ( especially if you changed the guide ) ----is just asking for trouble .

the concentricity of the 45--or 46 seating angle is so crucial on being at the very top of the valve and being in alignment for a correct seal for power and life ------there is no way i would not ever cut the seats with nice tight guides ----

i am really finding that with tight guides with a nice sharp valve cut and seal with the good ferrea valves and springs are really yielding some super life and power !! :thumbsup:





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