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  • Moderator
Posted

put in a 95 mains in today and...spot on sparky is a nice brown colour :)

went for a little ride, its quite loud so turns heads and I have to get used to this changing gear routine too, up and down the box all the time.

I think the running jet is a bit too large now, but I'm on WOT all the time anyway! :razz:

still need to sort out this dragging clutch as its hard to get neutral and you have to rev the engine to stop it stalling.

Posted

put in a 95 mains in today and...spot on sparky is a nice brown colour :)

went for a little ride, its quite loud so turns heads and I have to get used to this changing gear routine too, up and down the box all the time.

I think the running jet is a bit too large now, but I'm on WOT all the time anyway! :razz:

still need to sort out this dragging clutch as its hard to get neutral and you have to rev the engine to stop it stalling.

Well what did you expect from a 50 ?to cruise around in 4th LOL well its been quite the job you have pulled off why I am still wondering but your happy so enjoy the little toy.

  • Moderator
Posted

sorted out the dragging clutch, so its much better to ride.

I still think it bogs early doors, so I'll try different slow jets

  • 3 weeks later...
  • Moderator
Posted

I've been jetting the engine the past 2 weeks in between the rain drops, and finally got the slow jet dialled in but the mains are driving me crazy.

So far I went with a 95 and rode that a few miles and it went fine although a little slow. dropped it to a 92 and it ran like shit, so I upped to a 98 and that was a lot better. Got meself another jet kit and went for a 102 and it was a different beasty. the issue is it now vibrates, having no experience with Gilera's I wonder if I have too much fuel in there and its increasing the compression ratio or its normal and thats the was a 40 year old moped does!

I'll recheck the timing (although I've used a dial gauge for tdc) and try a plug chop. but these modern fuels skew the results as the plug looked fine at 98!

thoughts? ( about this and not random things)

Posted

To increase the compression you would have to increase the volumemetric efficency as well,is the carb bigger than stock?

What about splitting the difference and put in a 100 main jet or retard the timming closer to tdc. Ie if you have it at 4degrees btdc knock it back to 3 untill the motor is full broken in

All in all though it's solid mount engine so I would think that you will always have some vibrations,unless you can bore out the mountin bosses on the motor and stuff in some rubber mounts,But as this is just a get around type of bike ,not like your going to drive it 200 miles in a day on the freeway for hours on end is it realy that bad?

  • Moderator
Posted

To increase the compression you would have to increase the volumemetric efficency as well,is the carb bigger than stock?

What about splitting the difference and put in a 100 main jet or retard the timming closer to tdc. Ie if you have it at 4degrees btdc knock it back to 3 untill the motor is full broken in

All in all though it's solid mount engine so I would think that you will always have some vibrations,unless you can bore out the mountin bosses on the motor and stuff in some rubber mounts,But as this is just a get around type of bike ,not like your going to drive it 200 miles in a day on the freeway for hours on end is it realy that bad?

vibration not really too bad, but I didn't have it before.

if you have a certain amount of volume which is compressed by the piston,surely introducing more vaporised fuel with the same air will cause more of it to compress thus increase compression? Standard carb is 12mm i have a 19mm in ;)

What am absolute beaut

thanks Cal :)

  • Moderator
Posted

well I rechecked the contacts and they were closed up slightly so re-gapped, then redid the timing as it was too retarded.

WOW, It flies now and the ugly duckling is now a very fine swan indeed!

no bogging, clutch is slipping again as the new found power comes in and the vibration is a lot better too!

happy days.

I also helped a work colleagues lad to tune up his sr125 as it was dire.

bled the brakes, stripped and cleaned the carb and dialled it in, did the valves, air in tyres, chain lubed and tightened. he took a great interest in doing ita nd was a pleasure seeing him get something out of the day.

The bike now runs like a dream and stops like one too :)

Posted

it was too retarded.

Reminds me of someone i know :eusa_whistle:

glad to hear its all up and running :D

Posted

In a nut shell drewps NO,however the kenettic energy released would be greater with every little droplet of fuel you can get in. Provided it has enough time to burn

Compression ratio is dictated by a formula http://www.rbracing-rsr.com/compstaticcalc.html the source

The short story.

Displacement = (Bore ÷ 2)2 x 3.14 x Stroke x 16.387 Head Gasket space = (Bore ÷ 2)2 x 3.14 x Gasket thickness x 16.387064 Deck Height space = (Bore ÷ 2)2 x 3.14 x Deck Height x 16.387064 Compressed Volume = Head Gasket space + Deck Height space +
Piston Top volume + Combustion chamber volume
Uncompressed Volume = Compressed Volume + Displacement Compression Ratio = Uncompressed volume ÷ Compressed volume

Thats why a good engine builder will measure the cc's of each head pocket on a multi cylinder eng and match them all.

  • 3 weeks later...
  • 1 month later...
  • Moderator
Posted

just got a lafranconi competizione spannie off a fellow member the other day. the same as this fizzie

wonder if he'll hear me coming this time?

  • Moderator
Posted

got a call from the engineers today, he is recommending to write it off, then the cheeky fecker says its not on agreed value.

right, I have the paper here which begs to differ.

anyway, I'll buy it back as salvage and rebuild it

  • Moderator
Posted

Feckers tried to take the bike from red rose retrobikes today

Dave sent them packing

Posted

What 'engineers' are these then?, sound a bit shifty to me, something underhand going on here perhaps...

  • Moderator
Posted

got the bike back safely home. suddenly gone quiet :eusa_think:

Posted

what has ! the exhaust or the insurance..

  • Moderator
Posted

what has ! the exhaust or the insurance..

both

  • 1 month later...
Posted

Drewps

Any update...I just noticed your signature stating 5v (deceased)


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