1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Help Inline 4 slip on exhaust upgrade & FZR250 EXUP valve rattle repair

Discussion in 'Yamaha 250cc In-Line 4's' started by Brandon Otte, Oct 15, 2020.

  1. Brandon Otte

    Brandon Otte Active Member

    Messages:
    150
    Likes Received:
    30
    Trophy Points:
    53
    Joined:
    Feb 29, 2020
    Gender:
    Male
    Occupation:
    Plumber
    Location:
    Hamilton, New Zealand
    My Bike:
    Yamaha FZR250 2KR 88
    Hi everyone,

    I’ve been looking for an aftermarket slip on exhaust for my fzr250. I’ve come across many various makes and designs online ranging from dirt cheap to very pricey. I’d like the cheapest, easiest option. Biggest question really is the sizing and whether they will fit/slip on.
    Does anyone recommend any specific items for the little Yamaha with any experience. I did try remove the muffler which was deafening and illegal. I have thought about gutting my standard muffler but obviously it’s not reversible so if I muck it up.... perhaps buying a spare and gutting that one?

    And also has anyone had any experience repairing the EXUP valve - the annoying rattle at idle that is, works mint still.
     
  2. my67xr

    my67xr Bike Enthusiast Staff Member Premium Member Contributing Member

    Messages:
    4,308
    Likes Received:
    2,360
    Trophy Points:
    898
    Joined:
    Jun 18, 2016
    Gender:
    Male
    Occupation:
    Panel Beater, Spray Painter, Custom Fabricator
    Location:
    Adelaide, South Australia
    My Bike:
    Yamaha's , 1990 FZR250R 3LN3 , 1986 XT250TS 57R , 1984 IT200L 43G, 1976 IT400C 510
    There's a link half way down the page here for EXUP Maintainence
    https://2fiftycc.com/index.php?thre...-powervalve-information-and-maintenance.1099/

    The standard muffler was originally welded to the exhaust after the exup
    With the new muffler just measure the exhaust pipe where you want to slip the muffler over and buy that size muffler in the style you like.
    If the muffler you buy is a little tight to get over the pipe take it down to your local exhaust shop and have them flare the pipe just enough to be a slip on fit
    Some use 2x spring's and a couple of hook's that are welded to your pipe then you fit the spring onto the hook's to hold the muffler there, and some muffler's are simply clamp on

    @Linkin bought one of the JRE ? muffler's for one of his FZR's, also think another member used the same one more recently
    https://www.ebay.com.au/sch/i.html?_from=R40&_trksid=p2380057.m570.l1313&_nkw=jre+muffler&_sacat=0

    This might still be available too ?
    https://2fiftycc.com/index.php?threads/musarri-50mm-universal-slip-on-muffler.11064/
     
    • Like Like x 1
  3. gregt

    gregt Well-Known Member Premium Member

    Messages:
    165
    Likes Received:
    129
    Trophy Points:
    248
    Joined:
    Mar 26, 2016
    Gender:
    Male
    Location:
    Hororata NZ
    My Bike:
    many and varied
    I've repaired a couple of 400 EXUP valves. In both cases it was the bearing at the inner end - the small one - which had worn.
    I drilled the hole in the cast exhaust piece bigger and made a bush to suit. The holes wear out of round so drilling larger gets you back to a round hole.
    The bush has to be heat resistant and wear resistant. I used cast iron. An old (british) valve guide from the scrap box.
     
    • Like Like x 4
  4. Brandon Otte

    Brandon Otte Active Member

    Messages:
    150
    Likes Received:
    30
    Trophy Points:
    53
    Joined:
    Feb 29, 2020
    Gender:
    Male
    Occupation:
    Plumber
    Location:
    Hamilton, New Zealand
    My Bike:
    Yamaha FZR250 2KR 88
    So was that worn bearing causing your valve to rattle like a tin can at idle?
     
  5. Brandon Otte

    Brandon Otte Active Member

    Messages:
    150
    Likes Received:
    30
    Trophy Points:
    53
    Joined:
    Feb 29, 2020
    Gender:
    Male
    Occupation:
    Plumber
    Location:
    Hamilton, New Zealand
    My Bike:
    Yamaha FZR250 2KR 88
    @my67xr my muffler is standard and is slip on. I’ve found a LeoVince slip on muffler which I’ll pick up this afternoon. Im hoping it’ll fit, just winging it.

    30A43440-1249-4BA5-ACD1-3CBB6C88B4C7.jpeg
     
    • Like Like x 2
  6. gregt

    gregt Well-Known Member Premium Member

    Messages:
    165
    Likes Received:
    129
    Trophy Points:
    248
    Joined:
    Mar 26, 2016
    Gender:
    Male
    Location:
    Hororata NZ
    My Bike:
    many and varied
    Customer bikes. Heard them coming so simply said, I can fix that, you pull the pipe off and bring it in. Saved them money - and me time. Yes, it works. The inner bearing is a blind hole in the casting. Condensation, corrosion, heat and acidic gases all combine to give it a hard life. It's a steel pin in what i think is a nodular iron casting so very basic metallurgy.
    Anything better would be many times the price.
     
    • Like Like x 1
  7. ruckusman

    ruckusman White Mans Magic Master Premium Member Dirty Wheel Club

    Messages:
    2,306
    Likes Received:
    999
    Trophy Points:
    693
    Joined:
    Oct 1, 2013
    Gender:
    Male
    Location:
    Narrabeen, NSW Australia
    My Bike:
    Yamaha FZR250 3LN1
    Been a long time since I've had it apart, however when I looked into the EXUP for the rattle source and the bearing came out easily and was bronze - always meant to get a replacement but never got around to it
     
    • Like Like x 1
  8. gregt

    gregt Well-Known Member Premium Member

    Messages:
    165
    Likes Received:
    129
    Trophy Points:
    248
    Joined:
    Mar 26, 2016
    Gender:
    Male
    Location:
    Hororata NZ
    My Bike:
    many and varied
    Ouch. Bronze is not a good choice for a bearing there. Sure it was OE ?
    The ones I've dealt with - 400's and a couple of 1000's - were all direct into the casting, no separate bush.
    I haven't looked at a parts fische for the 250's so I may be totally wrong there.
     
    • Like Like x 1
  9. my67xr

    my67xr Bike Enthusiast Staff Member Premium Member Contributing Member

    Messages:
    4,308
    Likes Received:
    2,360
    Trophy Points:
    898
    Joined:
    Jun 18, 2016
    Gender:
    Male
    Occupation:
    Panel Beater, Spray Painter, Custom Fabricator
    Location:
    Adelaide, South Australia
    My Bike:
    Yamaha's , 1990 FZR250R 3LN3 , 1986 XT250TS 57R , 1984 IT200L 43G, 1976 IT400C 510
    The exup collar on my spare exhaust is either bronze or non magnetic stainless
    The collar seem's to be retained on the shaft, possibly from corrosion on the cast iron valve ?
    Bush inside the exhaust i'd need to clean up to see what it's made of


    20201017_142512(0).jpg 20201017_142540.jpg

    90387-106U7 Collar
    [​IMG]

    No real life picture's of the bush though, part's 11 and 15 below

    [​IMG]
     
    • Informative Informative x 1
    Last edited: Oct 17, 2020
  10. my67xr

    my67xr Bike Enthusiast Staff Member Premium Member Contributing Member

    Messages:
    4,308
    Likes Received:
    2,360
    Trophy Points:
    898
    Joined:
    Jun 18, 2016
    Gender:
    Male
    Occupation:
    Panel Beater, Spray Painter, Custom Fabricator
    Location:
    Adelaide, South Australia
    My Bike:
    Yamaha's , 1990 FZR250R 3LN3 , 1986 XT250TS 57R , 1984 IT200L 43G, 1976 IT400C 510
    Ok, after a quick vapour blast and a test with a magnetic pick up tool the bush is also non magnetic,
    infact the whole exup housing on the exhaust is non magnetic so i'm guessing stainless for the housing

    20201017_145749.jpg
     
    • Informative Informative x 1
  11. Brandon Otte

    Brandon Otte Active Member

    Messages:
    150
    Likes Received:
    30
    Trophy Points:
    53
    Joined:
    Feb 29, 2020
    Gender:
    Male
    Occupation:
    Plumber
    Location:
    Hamilton, New Zealand
    My Bike:
    Yamaha FZR250 2KR 88
    A9F6A435-22AA-4E81-B25F-337205B4CC81.jpeg @my67xr that cleaned up well with a blast! So I’m gathering I’ll need to replace the bush and collar? Parts 11 & 15... or as @gregt mentioned to drill out the housing hole and fit an oversized collar to suit?
    I would think(without prior knowledge or ever looking at my EXUP valve) I could replace both parts 11 & 15 without any machining - not that I would know...
    I fitted my LeoVince muffler last night after some slight modification. Went for a quick spin around the block and wow it sounds amazing!!! Pops and flames out the rear too :) I regret not wearing ear plugs as my ears were still ringing this morning. Went for another ride this arvo, with ear plugs, and sound track wise it makes a world of difference, not sure if it’s just the sound making me “feel” more power?

    I always tried wearing ear plugs to muffle the wind noise through my helmet but then I couldn’t hear the exhaust note. Now I can have plugs in and enjoy the pure inline 4 screamer soundtrack. I hope it doesn’t attract attention from bystanders though.
     
    • Like Like x 2
  12. Brandon Otte

    Brandon Otte Active Member

    Messages:
    150
    Likes Received:
    30
    Trophy Points:
    53
    Joined:
    Feb 29, 2020
    Gender:
    Male
    Occupation:
    Plumber
    Location:
    Hamilton, New Zealand
    My Bike:
    Yamaha FZR250 2KR 88
    @gregt I see you’re in NZ as well. Do you still work on exhausts, if so would you be willing to repair my EXUP valve for your fee if I could arrange postage? Providing I can’t do it myself.
     
  13. gregt

    gregt Well-Known Member Premium Member

    Messages:
    165
    Likes Received:
    129
    Trophy Points:
    248
    Joined:
    Mar 26, 2016
    Gender:
    Male
    Location:
    Hororata NZ
    My Bike:
    many and varied
    I'm in the South Island. I'd look for a small general engineering co local to you.
    Looking at the pics, I'd think the separate bush is a distance piece which limits endfloat. I suspect the plain pin on the end is actually the bearing surface.
    Material is probably Inconel. A high temp stainless alloy.
     
  14. ruckusman

    ruckusman White Mans Magic Master Premium Member Dirty Wheel Club

    Messages:
    2,306
    Likes Received:
    999
    Trophy Points:
    693
    Joined:
    Oct 1, 2013
    Gender:
    Male
    Location:
    Narrabeen, NSW Australia
    My Bike:
    Yamaha FZR250 3LN1
    From memory, the rust pitting on the EXUP valve itself is the problem, making it loose and rattle
    if inconel is available in a thin wall tube which could go over as a sleeve then drill the bearing to suit

    I don't see much point replacing the bush and bearing when it's the pin on the end of the EXUP valve which is the problem
     

Share This Page