XR200R Cylinder to Piston clearance

Discussion in 'Thumpers' started by Mcreviver, Jul 6, 2013.

  1. Mcreviver

    Mcreviver Adventurer

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    I tore apart my 96 XR200R to se what all the smoke was about and found a distinct lack of maintenance by the previous two owners. There are 7k miles on it and never once was the centrifugal oil filter cleaned. The oil pump is scored and the piston rings are shot. Cam chain guide is trashed too. P.O replaced the cam chain just before I got it and it ran okay for about 100 miles. I am going to put a 66 MM Wiseco piston in it and need to know what the recommended piston to cylinder clearance should be. The service limit is .10mm or .004" I'll figure .002" should be about right but I don't want to go too tight and risk an early seizure. Anybody want to chime in?
    #1
  2. whisperquiet

    whisperquiet Been here awhile

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  3. Mcreviver

    Mcreviver Adventurer

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    However it still doesn't answer my question. They are talking about small and large block V8 engines with .004" to .005" clearance. Honda specifies a maximum of .004" for this model. At that point it is worn out. So I am still thinking .002" will be sufficient for this size of bore. If I go less than .002" I would worry about seizure during break in. Yes, no ?
    #3
  4. Benesesso

    Benesesso Long timer

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    What does the piston/cyl. look like? Clearance?
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  5. ttpete

    ttpete Rectum Non Bustibus

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    If the engine is as nasty as you say it is, you need to do a complete teardown and also find out how much wear and taper the bore has. I'd also worry about the top end and valve guides and seats. It doesn't really sound like it's worthwhile to sink that kind of money into an old POS.
    #5
  6. MCCOYBOY

    MCCOYBOY Adventurer

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    The piston box will have the recommended clearances printed on the side of the box. It will be a forged piston and the clearances will be larger than if it was a stock cast piston. We use the info on the box when boring the cylinder.
    #6
  7. Mcreviver

    Mcreviver Adventurer

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    Thank you. That is the information I need.
    To another poster, I realized this old bike isn't worth the money to fix up. However, I restored the rest of it last year and it is like new externally. Once I have the engine fixed up I'll have 2 reliable on/off road bikes that I and a friend can go into the woods of central PA with. There is a photo elsewhere of my ST1100 along side of the two XRs.
    I worked for two different Honda dealers as a mechanic back in the 1970s and 1980s, so in my retirement this is one of my hobbies. It's also why I am M. C. Reviver. I revive dead MotorCycles. Thanks to everyone for the replies to this thread.
    Ron<On two wheels since 7/3/1964, about a quarter million miles ago.
    64 C110, 65 CA77, 69 CB750 (Sandcast), 78 CX500, 81 XR200R, 82 XL250R, 83 GL650, 97 VFR750, 2000 ST1100, 96 XR200R, 96 XR250L, plus bikes bought, repaired/restored and sold. 1 C110, 2 CT90, 1 CJ360, 1 XS400, 1 XL250S, 1 GL650 Silverwing.
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  8. qkenf4u

    qkenf4u Been here awhile

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    nice warm bike riding COTTONWOOD ARIZONA...
    :clap:deal was gonna say that but figured the first couple replies pointed at that suggestion but i was wrong.... :lol3
    as stated go with what SEIZCO tells ya on the box... :huh
    #8