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Help Me Please: Chain Guard Bolt

Discussion in 'Technical / Mechanical Discussion' started by Vivra, Oct 22, 2019.

  1. Vivra

    Vivra

    Current Bike (Optional):
    Honda CBR 600 RR
    License Currently Held:
    UK Provisional (CBT)
    Hello maybe a stupid question but i can't find answer in the internet, looking for size of a bolt that goes into chain guard maybe somone know the size of it?
    View attachment 33424

    Attached Files:

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  3. NorthCust

    NorthCust Active Member

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    Current Bike (Optional):
    2008 Yamaha R125
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    I think most of the little bolts around there are *i believe* M6 (diameter) x 1 (thread pitch), though obvs the lengths vary. I've been replacing mine with stainless ones where I've been able to.

    I have to do another oil change today so will check and confirm/amend.

    trick rearset btw ;)

    [edit]
    just checked and I can't really get to that bolt without pulling the rearset off which I'm not about to do, also one of the other bolts I removed from round there was corroded and the head broke off so had to drill it out..and that's also *really* not what I want to get into today, but it looks like the same size as the bolt behind the kickstand which holds the plastics on which, as I recall was an M6x1 with a 10mm socket/head. You can get similar bolts on ebay for a couple of quid - could be worth ordering one or two and compare? these are stainless allens but https://www.ebay.co.uk/itm/221307549544 or hex heads: https://www.ebay.co.uk/itm/150935671186
    Vivra likes this.
  4. Vivra

    Vivra

    Current Bike (Optional):
    Honda CBR 600 RR
    License Currently Held:
    UK Provisional (CBT)
    Thx for the replay, i was thinking it's m6 i don't know the lenght still, i order some and if they going to be too long i will cut the end, also looking for other bolts that i put some where and lost. Looking for this 2 bolts that covers rear sprocket (sorry for my bad english).
    1424124.jpg

    BTW my rear end look like this now ;)
    5125125.jpg
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  5. NorthCust

    NorthCust Active Member

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    Current Bike (Optional):
    2008 Yamaha R125
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    UK Full Bike
    heya, that sounds like a plan :)

    Be aware that the stainless bolts are *really damned hard* so trimming them on a grinding wheel is probably best if you have to..though that sized thread is used so much on the bike (and my scooters) that I just have a few bags with different sizes. If you're trimming them make sure to put a nut on them first before you grind/cut them shorter and then undo the nut off the end to clean up the thread so you don't mash up the soft aluminium casing with a badly trimmed bolt thread. Stainless will destroy aluminium if you're not careful and looking at how much effort you've put into making the bike look perfect it seems a shame to cheap out on a few bolts of the right size.

    I think for the chain guard they're about 15mm long (threaded section only not including the bolt head). You might be ok with a little longer cos I *think* they just go into the hollow swingarm casing.

    Those sprocket cover bolts are the same m6 thread, but have originally have a smaller (8mm socket) hex head - but again you can use stainless allens or whatever instead. I was trying to find them on here: https://www.motorcyclespareparts.eu/en/yamaha-parts/2008-yzf-r125-motorcycles since they usually have *everything* but haven't been able to locate the cover so far.

    I don't know the length of the sprocket cover bolts but I'm changing sprockets on sunday so can check then if you like. I *think* they're about 20mm (again not including the bolt head), maybe a little longer. Do check when buying the bolts - some sellers specify that the length includes the head and others it doesn't.


    Damn that's looking **clean**! so much detail and effort gone into it. Nice job :D

    Is that an adjustable rear shock I see? Looks like it's got adjustable preload.. where did you find that if you don't mind me asking?
  6. Vivra

    Vivra

    Current Bike (Optional):
    Honda CBR 600 RR
    License Currently Held:
    UK Provisional (CBT)
    THX for your tips, i think i will gonna post a video after i finish my bike i was rebuilding it after it was stolen :( almost all rear end is new (chain guard, wheel sprockets, wheel nuts, bearings, wheel bolts, new swing arm, new shock absorb and more that i don't even remember) the shock absorb is YSS i bought it from ebay paid 225£ in total with postage - https://www.ebay.co.uk/itm/YSS-Rear-Shock-Yamaha-Yzf-R-125-2008-2015-Shock-Absorber-271/153180172688?ssPageName=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2649
    If you check your bolts in sunday i will be very appreciate. image1.jpeg image2.jpeg
    Little sneak peek to the front :)
    image0.jpeg
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  7. NorthCust

    NorthCust Active Member

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    thanks for the ebay link on the shock - not cheap but it looks like the right thing. Is it adjustable damping as well as preload? I see there's a little bolt near the top.

    I think my rear damper travel has actually been ok but I've been learning lots from the Dave Moss Tuning videos and from what I can tell by the "ziptie on the forks test" I'm nearly thru my fork travel and have never ridden more gently...so I may need to look into something there. There's adjustable cartridge dampers for the late model forks but none for the early ones as far as I can tell. I'm hoping slightly thicker fork oil will do the job as it would be a hell of a lot cheaper ;)

    wow you really have done every last trick part on that bike haven't you :D They even look to be titanium rear sprocket bolts?

    Those two bolts are 16mm threaded section, 21mm total. They could easily be a couple of mm shorter and still be fine as they only hold the plastic sprocket cover on.

    Looking forward to pics/video of the full bike :)

    20191027_150504_www.jpg 20191027_150440_www.jpg
  8. Vivra

    Vivra

    Current Bike (Optional):
    Honda CBR 600 RR
    License Currently Held:
    UK Provisional (CBT)
    THX for the picks i order the bolts hope they gonna be good :p Titanium swing arm bolts and titanium rear sprocket nuts, new galfer front and rear disc, chain etc... have galfer pads but im gonna put brembo pads because i like brembos a lot :D there is a adjustable damping (knob) and the bottom max is 60 clicks and at the top there is a compression damping that you need use a (thing, key) that is inculded in package but i think you can adjust it with normal torx head screw driver.
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  9. NorthCust

    NorthCust Active Member

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    > Titanium swing arm bolts and titanium rear sprocket nuts, new galfer front and rear disc, chain etc..

    wait you mean the big main swingarm bolt is titanium too? I did not know that was available. lol can't believe you've got me looking up titanium bolts ;)

    I suppose with the bolts you're looking for there would likely be titanium ones which would also fit rather than stainless and given they're not really load bearing, you may as well have the weight saving, plus they also don't corrode. It's only tiny but it does all add up. It might also be worth replacing the two little bolts on the front sprocket - sounds ridiculous but reducing the weight of anything rotating, even just a tiny bit could be worth it because of how the forces are magnified with movement. They are also not load-bearing, they just hold the clip in place so don't see why they couldn't be replaced (unless you already have?). TITANIUM ALL THE THINGS ;)

    > there is a adjustable damping (knob) and the bottom max is 60 clicks and at the top there is a compression damping that you need use a (thing, key) that is inculded in package but i think you can adjust it with normal torx head screw driver

    oh wow so you have preload on the spring collar, rebound damping from the knob *and* (compression?) damping from the little torx key? That's really good - I didn't think I would find anything that advanced for our bikes! great find, thank you. It's not something I can afford to do right now but once she's run in again and I get near a track, making sure the suspension setup is spot on was something I wanted to look into.

    I've always found taking the time to get the suspension setup just right has always been *really* time consuming (much easier in gran turismo haha) but many years ago when I did it on my golf it absolutely *transformed* the handling. My friends laughed that I spent several weeks taking the front end apart and rebuilding it over and over again (swapping springs was expensive and not easy, even with coilovers) but eventually I got it right and that day I spent hours just sliding it round roundabouts and laughing like an idiot. It was so nicely balanced, especially for a AWD (well..FWD+R). Hopefully it'll be a bit easier on the bike at least ;)
  10. Vivra

    Vivra

    Current Bike (Optional):
    Honda CBR 600 RR
    License Currently Held:
    UK Provisional (CBT)
  11. NorthCust

    NorthCust Active Member

    Home Page:
    Current Bike (Optional):
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    ah ok nevermind then.. I've recently replaced my axle adjuster bolts with stainless and just put new sprocket and chain on, not in a massive hurry to re-do those. Thanks :)
  12. Vivra

    Vivra

    Current Bike (Optional):
    Honda CBR 600 RR
    License Currently Held:
    UK Provisional (CBT)
    43242.jpg
    4234.jpeg
    Small update new brake one bracket painted from silver to black and other from gold to red.

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