winter upgrades and engine rebuild

just started to do a few over due jobs on my lui which include engine upgrade and rebuild plus the upgrade of the forks. first off is the engine upgrade, a new 50mm wisco single ring piston and rebore to suit. head is one that i got off daz h with the plug coming out at the flywheel side and has a better shape to the combustion area. new long con rod, some mad porting and an lth reedvalve. a 26mm oko flatslide carb. varitronic ignition. the allspeed exhaust that i made will used and tried on a dyno to see if its any good.engine is allready stripped and crank should be back before xmass . ignition back plate is fitted i just need to weld the vega boss to the flywheel.

the clutch has had some treatment aswell to handle the expected double figure hp

i have drilled some big holes in the sprocket to reduce weight and let gear oil flow better, will also be going 4 plate using series 3 thin steels with a couple of mm skimmed out of the sprocket . also going to try a starstream 14 tooth front sprocket, they fit and line up just the same as the vega 13 tooth sprocket they also have a cush drive. i might be able to use the same chain as it is stretched now if not i will get one made with a half link.

forks were stripped this aft and not before time as the lower buffers were buggered also the link bushes are badly worn. upper damper brackets are now welded on and were dropped off at my local powder coaters to be re done. the push rods are badly worn aswell , so i have ditched these and cut some new series 3 rods down and also cut some new standard series 3 fork springs down to the same length as the lui springs. they fit in the forks without any fettling, it should improve the front end no end. will be having a look at the link bushes tomorow, i think i might do away with them and see if i can find or machine down a stainless bolt that will take the space of the bush, then just enlarge the bolt holes through the forks. the brakes are spot on so wont need to do owt to them

i have done away with the rear light and fitted a vega light and number plate holder. just need a rear light.

will put a few pics up tomorow nite, but here is a pic of the rear sprocket after some weight loss

Very interesting, what cc's are you expecting? Have you seen the scootRS copy of the LTH reed block? I think they use the name Atomic, it looks ok and as you could expect is a bit cheaper i was thinking of using one when i get round to changes on mine.

i allready have an lth but have seen the scootrs atomic ones they look good for the luna/j conversions. cc wise i think it will be around 85cc, i wont gain cc with the longer rod (would only gain with bigger stroke or increase in cylinder diameter) but it needed a new big end and my local 2 stroke expert had some rods that were ideal to go with the wisco piston and same big end pin and rod width size as the standard vega but with a bigger bearing and moto x strength . piston was around £50, good quality gol brand vega pistons are £40 + and the rod was £25 so a reasonable cost to upgrade . + rebore and tune and cost of crank re build of course, but it needed a rebore and piston anyway (bad piston slap and a rumbeling big end). wil get a few more pics up tomorow. cheers siimon

Thackers wrote:Very interesting, what cc's are you expecting? Have you seen the scootRS copy of the LTH reed block? I think they use the name Atomic, it looks ok and as you could expect is a bit cheaper i was thinking of using one when i get round to changes on mine.

here are a few more pics

fork springs


varitronic stator


fork link using the inner stainless sleeve and bolt from a series 3 fork link, a straight fit no fettling


will do away with this

you've been busy
them s3 rod springs look a lot beefier, think i have a set somewhere i can chop up.

Lookin' forward to see how you get on with the rear sprocket/clutch idea - like the
sound of that

Some good ideas there Simon, i've read about the spring upgrade idea before, some said it made the front too tight/stiff. If you take out the two outer bushes/sleeves on the fork link and have the stainless part, wont it need lubricating as it's metal to metal? Or am i way off beam ??

Thackers wrote:Some good ideas there Simon, i've read about the spring upgrade idea before, some said it made the front too tight/stiff. If you take out the two outer bushes/sleeves on the fork link and have the stainless part, wont it need lubricating as it's metal to metal? Or am i way off beam ??

the standard springs on my lui are realy cack, so i thought i would give some standard series 3 one a try, not the uprated progresive type. so will have to see. and yes you are right about some lube on the bushes. i wanted to use and still might use some early series 1/2 fork link bushes as the are bronze and greased via a grease nipple on the end of the bolt or i could drill the stainless ones i have.

got my forks back from the powder coaters today and rebuilt and fitted here is a pic or two, and i drilled the fork links for greasing





had ago just free wheeling round my workshop and slamming on the front brake and its spot on way better than the standard set up , will fit some dampers on tomorow . was also looking at some pitbike rear shocks as a good replacement for the shit standard one. seen a few at around 280mm to 300mm with 250lb spring and fully adjustable http://www.ebay.co.uk/itm/290813544653?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

just waiting for some clutch plates to arrive aswell so i can finish that off

That is sooooooooooooo clever, it sometimes makes you wonder why Innocenti didn't do things like that. So the series 3 springs worked out, another step forward. I have a set of front forks i'm getting the damper mounts welded on, when i get them ready to go on the bike i'll be looking into the spring trick. Thanks for sharing the ideas. There's some clever people on here

he's a clever lad that simon

goods mods simon .very clever man

...looking good,sprigs might be too hard ? [hope not] I thought about putting in some 10mm washers to stiffen the pre-load and skim off a bit of the bottom buffers and had an idea to try some 'j' links for more ride height..? Clutch sounds good,make sure they're surflex...I was going to use a gp 5 plate reduced to 4 for vega..? [when/if it breaks]... enjoy!

ey up joey

my set up will be more of a road/race set up . and now due to loosing a stone (still need to loose another ) the front end is spot on, was bottoming out and wheel leaning over and catching fork leg every time i rested me fingers on the brake leaver. as you need a road/ off road (beamish trials, scotish 6 day etc) set up soft and longer travel is what you need . i have orderd a newfren 5 plate set up 1mm steels and just under 3mm corks from scooter restorations . everyone seems to be out of the bgm red corks (2mm i think ?) so this will have to . will up date as and when . cheers simon

rev/temp gauge fitted and will now be going down the px 12v conversion as i dont think the gauge would work with the varitronic. i have fed the wires under the frame near the brake light wires and will go under the mag housing and tie in with the stator wires to the junction box to keep it tidy

fitted some dampers today and had a freewheel round my workshop and slamed on the front brake a few times, what an improvement . crank is nearly ready had to have the sides of the rod ground down a bit to get it in the webs, i have not seen it yet. and i best get on with the clutch because i have the ultimate madcap conversion about to take place a cylinder kit with 14bhp to 16bhp straight out of the box. will be fitting it tomorow, dry build on another case . also looking to see if it can be tuned anymore i am sure it can be done