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  • #16
    Originally posted by Brian Thompson View Post
    Nice pic Colin.

    A while back I posted some other pics of Derek's Greebsa as a 'Non-Greeves Engines' thread, showing it in both it's original form (as in the pic you posted above) when it was known as 'Red', and following Derek's recent smashing restoration and the change to BRG. There is also a link to a YouTube video of Derek starting the bike up! I've merged the post into this one and deleted the original thread-see below;

    Brian.
    Oh, right, thanks Brian, I just happened to come across the pic while looking for something else and thought Dave might like to see it. Forgot you'd already flagged it.
    Colin Sparrow

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    • #17
      Hi Dave, just caught up with the additions, sounds like you are steaming on, good on yer. Don't know if you intend running it at Mortimer at all, it's a great track by the way, but their own "Originals" Pre60 section draws the line at electronic ignition! It won't stop you racing there mind, so dont' let it stop you continuing or enjoying racing it once finished. I'm hoping you can make it there for at least one meeting as it's about midway between the two of us so theres a chance we can say hello. I usually make it there on a couple of occasions each season. Keep up the great work, hope to see you there.

      Originally posted by dave higgins View Post
      hi chaps.
      Sorry to have not replied, probs with computer.
      Right from the start the bike was going to be a pre 60 as i have already got a bsa c25 for pre 65 & the griff for the pre 74, so that is the reasoning behind it.
      The amca classic rule book says that all c15 dizzy engines are pre 60 complient irrelative of year, as are c25 engines pre 65 complient. because the c15 dizzy was just pre 60 you are allowed to use any post dated engine because the design was concurrent up until the side points model.
      On the point of oil in frame, its a non starter i`m afraid as the oil capacity is a minimium of five pints & if anyone can squeeze that into the old greeves frame, call me because i can get work for you as a magician!!!.
      If you don`t have the oil tank capacity your oil gets to hot & burnt oil has the lubricating qualities of sand, so its going to have a period looking tank tucked in there somewhere.
      I have just fitted a tasty little cam, bored it & fitted elec ignition, a few other tweeks & the motor is ready, its going to be running on methanol which i`m ( hoping ) will give it some proper grunt, thanks for the interest lads, i`ll keep you posted. dave.

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      • #18
        Thanks adrian, yes i will be riding at mortimer & looking forward to it!!!!!!.
        I did think the lecy ignition might be a problem & not sure of the pre 65 regs, prehaps using it in the pre 65 class for that meeting or is that out as well? i don`t know without reading it up, but again the amca states any internal engine mod is ok!! strange.... as the first 59 c15s were a self generating system that is not a million miles from what i have just fitted as i still use the the alternator & distributor, just got rid of the points & battery & use diode box instead.
        Anyway i`ll be there! ready & willing & my camper vans always got hot bacon buttys & tea, so your always welcome to come along & buy some!!!!:... i`m joking.
        Will say though, that the conversion has put a few pounds of weight on the bike & be interesting to see how it handles against the lighter hawkstones.
        Talking of weight! if i get on the exercise machine now & with these new bickers bars!, its just possible that you might, just might hear a bit of thunder behind you!!:....

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        • #19
          Extra weight shouldn't be a problem, Dave, it's the distribution that is more critical, and the power-to-weight effect of using a thumper engine. In fact, the Hawkstone will probably benefit from a bit more gravitational assistance. The two-strokers tend to be a tad skittish, in my experience. Certainly, my original Greeumph wasn't a problem back in the 60's, and the unit Triumph content of that was a good deal heavier than your C15 is ever likely to be.

          Good luck with giving young Adrian a run for his money at Mortimer, but stay well clear of his back wheel!

          John R

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          • #20
            Links To Related Threads About Dave's Greebsa Project.

            There are a couple of related threads to this topic posted elswhere on the forum, and rather than merging them with this thread I thought it would be easier to post links to them here, for ease of reference. See below;

            C15 Tuning; http://www.greeves-riders.org.uk/for...ead.php?t=2302

            Greebsa (Terry Weedy Built Project); http://www.greeves-riders.org.uk/for...ead.php?t=2174

            Brian.

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            • #21
              Back wheel eh!.
              Thanks for the advise john, sounds like a tale of bitter experience there somewhere!!!.
              Going back to the weight issue, i was half hoping that the extra pounds would make the front end perform a little better, so i`m happy that you found the same.
              The bulk of the weight is over the crank area & that is central to the wheel base, so stick a bit of rider weight on, yeah it should be ok.
              I bet your old greeumph was a bit of a awesome beast though, nothing like a triumph twin opening up down a straight, especially one with straight thru tubes.
              And as for adrian, well if i can`t beat him by cheating fair & square then i`ll have to knobble him in the pits. dave.

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              • #22
                What, with dodgy hot bacon butties?

                Good Luck!!

                John R

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                • #23
                  It's only the internal Mortimer Pre60 series that outlaw such ignition the remaining classes are quite ok, and as they run there own series alongside the other "Dodgy Pre60's" then you can enter in the Pre60 and Pre65 too!
                  Shouldn't worry too much about my rear wheel, it's only a skinny 3.75 x 19!
                  A bit like me really, so if you're after losing a few pounds so we're on an even power to weight ratio, then you may need to do some serious dieting! Not to many Bacon Butties Thanks for the offer of one by the way, sounds delicious, but I have to watch my figure you know. Well, if I don't nobody else will.

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                  • #24
                    Dave,
                    I don't know your build but I would suggest that to get the same power to weight as Adrian on a pre 60 you would either need a 650 twin or have at least one major limb removed.

                    Druid

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                    • #25
                      . Such a subtle wit, Druid.

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                      • #26
                        Hi everyone.
                        Just a small update on my thumper project, everything is going to plan, but has slowed down a bit due to redundency , thats the down side, on the plus side i`ve found that it has accelerated my race fitness weight loss program no end .
                        But everything is sorted & back on track now & should be finished by end of feb.
                        Was not totally happy with the motors bottom end being strong enough & stripped it again to beef up the timing side main bearing, £175 ....!!!! (ow much) ?.
                        but where do you stop with an engine? i don`t want to be stripping it mid season so its all or nothing!
                        Hopefully get some more pics on soon, but needing a good tank if anyone has anything available. dave

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                        • #27
                          Sorry to learn of you losing your job Dave, by the sound of it that bearing might have taken a large lump of any remuneration package offered! Looks like you'll be well sorted by the time the season comes around though. Let's hope for some warmer weather to tempt us out of hibernation, can't wait fo the lighter evenings to come round again! Good luck with the rest of the build, can't help with a tank I'm afraid but I'm sure something will surface before too long. Are you going to the AGM on April 3rd, it's always a good day out and the best event for Greeves spare parts?

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                          • #28
                            Hi Adrian, no renumeration i`m afraid, the whole company went pop, but they did lend me a pair of boots to walk home in!!.
                            On the bike front, it is looking really good & apart from a few small adjustments when the engine goes back in, i can`t see any problems arising.
                            What i will have to get machined up though is a longer rear wheel spindle, i`m running a pie crust/ paddle hub with the 1957 scramble swing arm which is 8" id & i believe the hawkstone arms id is a 7".
                            But going back to the bearing, thats a frightening price isn`t it for one needle roller & sleeve, still you know me! i`m not going to keep on about it, ( at least Dick Turpin wore a mask!!! ) enough said.
                            The agm sounds good & i am hoping to attend, be a good chance to put a few names to faces & call a few faces a few names, so i will see you all there.
                            As for the start of the season, can`t wait to get started, winter drags, i think we will all be glad to get back on the dirt. dave.

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                            • #29
                              When I fitted a needle roller to C15t in 1968 it cost £18.00 , that wasn't far off a weeks wages then .

                              Chris

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                              • #30
                                Nice one chris, you haven`t still got it have you? .... dave.

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