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  #31  
Old 06-02-2010, 06:43 PM
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Hi, well you got the bike up and running again, and it is looking good, its a gerat feeling when it starts first time after all that work.
Good to know that you are impressed with the kit, you will now have more time on your hands, now you will not be cleaning and adjusting the points .
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  #32  
Old 07-02-2010, 03:27 PM
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ok, it looks like I spoke too soon when I said I didn't have any teething problems

I took the bike out for a spin last night to let it stretch it's legs properly & all seemed to be well, running nice & responsive then after I'd done a few miles it seemed to loose power & it wouldn't rev past 5,500 rpm

this engine doesn't produce it's peak power till 6,500rpm & will normally rev up to 8000 & beyond so as you can probably guess it felt like it was strugling a bit

I had a similar problem with it once when out one day & the air fillter fell off making it run too lean, I had a quick look & it was still there so it wasn't that,

I can well imagine that it might be running lean now the system is running to full speck, but I can't fathom why it was all running great & then sudenly lost power like that

I've just taken it for another spin today to see if it runs better when cold then fails as it warms up but it's still the same as it was last night

this would normally be the time when I check to see if the points had slipped again but there is nothing to slip with this one

it still starts 1st kick, revs up freely, & idles well

oh well, I guess it's back to the drawing board eh?

I think I will raise the float hight a bit to keep the fuel level up & lift the slide needle one notch to richen things up in the mid rainge & try it again

I have a 105 main jet in there at the moment & the only other sizes I have are 123 & 140 with nothing in between as I haven't been able to track any down yet
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  #33  
Old 07-02-2010, 04:45 PM
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I forgot to mention that I have actually fitted the expansion chamber now

here it is,



it looks a bit combersome but it makes a big difference to the performance, putting my tool bag back on there should hide that horrible bracket

I raised the float & needle as planned & fitted the 123 main jet, & oh boy, what a difference,

it pulls like holy crap through 1st, 2nd, & 3rd, & leaves every thing a long way behind at the lights upto 45mph, which is rather fun, & it revs out at 7000rpm

4th gear isn't so hot though, it still pulls like a train upto 5,500rpm but it doesn't seem able to pull through that point, but it will do that just aswell up hill as it will down hill so it isn't over geared, just has a bad flat spot & top speed seems to be about 53ish

Last edited by mr ripley; 07-02-2010 at 05:06 PM.
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  #34  
Old 07-02-2010, 08:49 PM
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Hi, bit odd that if it was going ok on the first test run, and now things have changed, that makes you think of a fault, or is there something you did after the first run?, it makes one think its not down to tuning.

Still it sounds like you are getting there and it must be a good feeling to burn off all that traffic .
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  #35  
Old 07-02-2010, 11:03 PM
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yes it was pretty odd,

I hadn't done anything to it between rides & it had been running nicely up to that point,
but I had been riding it through the town where I was keeping the speed down so maybe I didn't notice it had a problem untill I got out onto the open roads & tried to open it out a bit, where I could use top gear

the strange thing is that after the 1st ride I checked the plug & it looked quite pale, but this morning when I checked it after last nights ride it was really dark & sooty, so the way it runs sugests a weak mixture but the plug says otherwise but richening things up has helped

I kinda broke my own number one rule today aswell which is, when making adjustments, never alter more than one thing at a time

then you can see how each thing effects the running seperately & which adjustment makes the biggest improvement

so, although adjusting the float, needle, & main jet all made a big difference, I'm not sure which one helped most

I'll go in there tomorrow & put the 140 main jet in & see if that helps or pushes it over the top

oh & yes it felt fantastic to leave the lights so quick, I was in 3rd gear doing 45 already when I looked in my mirrors & the car along side me hadn't even got accross the junction

I had a sudden moment of panic thinking I must have jumped the lights
but he soon caught me up & shot past me looking pretty anoyed that I had left him for dead
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  #36  
Old 09-02-2010, 01:29 AM
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I had to pop out to the local bike shop to get a side light bulb & a new breaklight switch so I popped in the 140 main jet before I set off

it absolutley killed it

it was fine up to half throttle & then it just started spluttering & tried to die, so I had to ride the 5 miles to the bike shop at half throttle, but I could still hit 50mph

while I was there I bought one of those k&n/s&b (can't remember the make) cone shaped power fillters for it, you know the ones,

I put that on before setting off on the home journey, instead of the old BSA pancake fillter I had on it, & it took off like a scalded cat again,

slightly calmer through the mid range than with the 123 jet & it still wouldn't rev much over 5,500 in 4th with a top speed of 52, but I got the impression from the way it felt that if I had found a decent down hill stretch it might have picked it's feet up

one thing I did notice is that I used to be able to hit 55mph in 3rd gear when it was in the old frame where as it strugles to hit 45 now, so I checked what sprockets I have on there at the moment & it's 16 front 53 rear (3.3125:1) it used to be 16/49 (3.0625:1) in the old frame, which can make a very big difference on a low powered machine like this

so I think, if I can track down a 49 tooth sprocket for this REH hub then we should start seeing the proper performance for this engine, & by my calculations would put the top speed at about 62 @5,500rpm in 4th (minimum requirement for a motorcycle A1 test), then if I can just make it rev out in top we should be onto a winner

on another note, the bike shop I went to is the same shop that sold this bike to its 1st owner back in 1974 & the bloke there was saying it's sacralige for me to be riding round on this bike as it was probably the best scrambler made at the time

I think in it's current state of tune it probabley could be competetive if entered in a classic scramble, as they rely more on acceleration & low down power rather than the top end that I'm hoping to achieve

Last edited by mr ripley; 09-02-2010 at 01:35 AM.
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  #37  
Old 09-02-2010, 06:49 PM
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Hi, well i dont know much about bikes, and we have never had much dealings with them, however a garage we go to a lot, Guys name Andy Carter, just over the hill from me, this Guy is a top scrambler and would know all there is about bikes, scrambing, tuneing and gearing, you may know of him, from mags, he would know who to get parts from too.

He may well come here to the forum, and i would be happy to ask him any thing you would like to know, me or Tim go there most weeks, the scrambler he uses is with a type of side car, dont rember what they call them,, ?, chairs or something i think,.

His dad had bikes also, and Andys Daughter rides bikes too, scramblers .

Bet he would know why it was one of the best scramblers, will ask him about your bike when i next see him.
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  #38  
Old 10-02-2010, 01:07 AM
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hi Gibb,

I have a chair that'll fit on this bike but the kickstart is on the wrong side so I couldn't start it if I put it on there

if you think your guy over the hill might know where I might get parts for this I would be very greatfull

it's a 49t sprocket for the REH conical hub with 5 inch center, & bing type 53 carburetter jets, 130, 135 main jets & 35, 40 pilot jets I'm after

or even if I could just get part numbers I might have an easier time tracking them down
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  #39  
Old 15-02-2010, 10:37 AM
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you all know the saying about how some thing is like wating for a bus.. nothing for ages then two come at once,

well, I just had that very same experience

I've owned this bike since early 2002 & I've never seen another one or ever expected to see one, then I go to a show & there's two of them sat next to each other



an early, Robin Goodfellow model with the fiberglass tank & a 1974 David Brand model with the alloy tank, the same year as mine

unfortunatley they were all packed in pretty tight so I couldn't get better photo's, & the owner was nowhere to be found so I didn't get chance to chat to him about them either
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  #40  
Old 15-02-2010, 07:18 PM
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Hi What an amazing thing, to go to a show and find two, two red bikes also, maybe the same owner.
Would have been nice for you to have had a chat with him, and tell him about the forum, was the show on the weekend.
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