Just a Re-Commission

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Viewing 15 posts - 16 through 30 (of 38 total)
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  • #12885
    Michael
    Participant

    Hi Mike,

    well, not my style, but for me it mustn’t be the original ones.

    If they produce a good sound it is a good choice 😉

    BTW: Is there any regulation in the UK that says that this kind of change must be noted in the papers ?

    Doing such a change in Germany, it will be necessary to have a “driving noise” measurement (passing by two microphones in 10 m distance to each other at full open throttle, starting with 50 km/h / 35 mph in second gear).
    Price for that approx 300,- Euros.
    Outcome unknown until you get the result, but you have to pay for it anyway ;-(

    Good luck !

    Cheers, Michael

    #12900
    Mikeonabike
    Participant

    Wow Michael that sounds expensive and complicated, There in no regulations here on old bikes like these but the newer ones must by law have a stamp on the exhaust to show they are up to a certain standard (Regarding noise pollution). However noise does not seem to be policed so people tend to buy “Track only” pipes and use those.
    I am not a lover of noisy bikes on track or off unless they sound nice (Read big low reving twins)

    #12877
    Kaptainkwak
    Keymaster

    My belief is that pre 1983 noise regulations do not apply. After that I believe now it is at the examiners discretion. I always get an advisory on the loudness of exhausts on all my bikes including the ZRX which is not stamped.

    #12901
    Mikeonabike
    Participant

    Well back to it after a 9 week brake, bit of a problem getting the rear brake to master cylinder to bleed, I had rebuilt it so I knew it was Ok, tried pressurising the reservoir from the top but that didn’t work very well so I connected up the calliper and put a rubber pipe onto the bleed nipple and pumped air in from a foot pump which went right back into the reservoir above the oil, releasing the pump sent brake fluid down the pipes like a rat down a drain pipe!!
    I do not recommend anyone ever does this as there is a possibility the master cylinder could explode.
    All that is to do now if fit the fuel tank, seat, side panels and sort out the exhausts.
    It could be MOTd by the end of the week 🙂

    #12902
    Mikeonabike
    Participant

    Started it up today, sounds fine.
    Also sorted out insurance which will start at the end of the month! 🙂

    #12903
    Mikeonabike
    Participant

    Another old girl on the road, Booked in for an MOT in the morning.

    #12904
    Mikeonabike
    Participant

    MOT passed with only one advisory for “noisy exhaust”
    Not sure where I am going to go with the exhausts now, I dare say it sounds great at a quarter of a mile away but it’s just way too loud for me.
    I prefer to be seen going rather than heard coming!!

    #12886
    Michael
    Participant

    Hi Mike,

    if you like the classic way this is the best one I can recommend:

    https://www.louis.de/en/artikel/universal-auspuff-conic-long/10027110?list=157529144&filter_article_number=10027110

    This is the long version I describe.
    A shorter version is available as well, but the sound is not so good as with the long ones.

    Affordable price, acceptable quality, low noise, but good deep sound when idling.

    In the end at factory noise level.
    It is possible to get both versions legalised to a Twin in Germany, so in the UK it is rated as a silent silencer, for sure 😉

    Cheers, Michael

    #12905
    Mikeonabike
    Participant

    Hi Michael
    I had a go at it today, I turned some large washers down and welded them inside out of sight.
    Its knocked a few decibels off the top so they will be ok for now.
    I have a 1963 CB72 to get on the road now, I was going to use these same exhausts on it but I don’t think I can live with them at 10,000 RPM, looks like thats going to get a pair of Honda 250G5 upswept silencers that I have been keeping for a rainy day 🙂

    #12906
    Mikeonabike
    Participant

    Hi Michael
    I had a go at it today, I turned some large washers down and welded them inside out of sight.
    Its knocked a few decibels off the top so they will be ok for now.
    I have a 1963 CB72 to get on the road now, I was going to use these same exhausts on it but I don’t think I can live with them at 10,000 RPM, looks like thats going to get a pair of Honda 250G5 upswept silencers that I have been keeping for a rainy day 🙂

    #12878
    Kaptainkwak
    Keymaster

    That’s a beautiful looking bike Mike.

    Well done and congratulations on a deserved MOT.

    #12907
    Mikeonabike
    Participant

    Thank you KK

    I will not get to ride it properly until I tax it starting April.
    Got a lot of work to do now on a 1963 CB72 that I have bought to be my small bike for summer.
    I always have a small bike for riding around the country lanes on summer evenings, usually its my CD175 which also doubles as a trackbike!!

    #12879
    Kaptainkwak
    Keymaster

    Credit where it is due Mike.

    I don’t think ive ever seen anything like a CD175 doing things like that before. That is amazing in itself and worth double respect.

    #12908
    Mikeonabike
    Participant

    Hi Guys, Thought this KZ was a bit slow, I found the reason for it, New front 17t sprocket arrived this morning so straight into the workshop and that’s when noticed it had a 40t sprocket on the rear!! anyway I will try it with the 17 and if I am still not happy I can change to a standard 38, cant go any larger on the front as the wheel is as far forward as it will go.
    I will post a video of it running some time in the future, sounds nice (If a little loud).

    #12887
    Michael
    Participant

    Hi Mike,

    having a 17/40 transmission that may be the maximum a “106 increment chain length” will allow.
    Going to 38 teeth sprocket in the rear should allow to go for 18 teeth front sprocket (if possible, as discussed in other thread).

    Good luck !

    Cheers, Michael

Viewing 15 posts - 16 through 30 (of 38 total)
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