lambretta 290 rotax

[holty]

no worries

cheers andy, the beast is in march edition of scootering by the way,
some more pics
IMG_1725_zps0ssrnlk4 by stephen holt, on Flickr
IMG_1722_zpsu0s1igd4 by stephen holt, on Flickr
IMG_1723_zpsddyxrlcs by stephen holt, on Flickr

[holty]

welded the water feed pipe onto the exhaust flange, then welded a stub on for the exhaust, then turned it down on my lathe as the heat distorted it, i will need to weld another part to the exhaust stub later on will include a groove for a seal.
IMG_1727_zpspqbsu1c1 by stephen holt, on Flickr
IMG_1728_zps6bge9x73 by stephen holt, on Flickr

[RManson]

Can't wait to see how you get on with this! Will be great to see how yours stays together and what solutions you come up with. I like the coolant inlet in the barrel, makes life much easier as opposed to welding/machining the crankcase. Keep on it!

[holty]

Can't wait to see how you get on with this! Will be great to see how yours stays together and what solutions you come up with. I like the coolant inlet in the barrel, makes life much easier as opposed to welding/machining the crankcase. Keep on it!

hi ryan, thanks for that, its was your rotax thread that influenced me to go in this direction, hows your going ?
holty

[holty]

decided to cut my cylinder head in half tonight, so out with the grinder and cutting disc, once i had cut off the piece i didnt want i decided to use a milling bit in my lathe and clean it up a bit, ready for welding up the holes.
IMG_1733_zps56qf7zgv by stephen holt, on Flickr

[RManson]

Fired it up a few times and been chasing little things endlessly! Should have an update shortly.

[holty]

Fired it up a few times and been chasing little things endlessly! Should have an update shortly.

oh good,its a popular thread, someone is always looking at it, no more progress on mine yet, should have my head back soon.


heres some pics of the case before its welded
IMG_1791_zpsqmmuzicm by stephen holt, on Flickr
IMG_1790_zpsoq23xhaq by stephen holt, on Flickr
IMG_1789_zps4errkre2 by stephen holt, on Flickr

[holty]

ive got hold of a scrap rb cylinder and cut off the part that houses the reedvalve, more cutting and shaping needed yet, heres roughly where its going
IMG_1812_zpspczwcvy5 by stephen holt, on Flickr
IMG_1814_zpszsmcack3 by stephen holt, on Flickr

[RManson]

Are you planning on modifying the frame to clear or are you going to build the intake to suit? If I were to do it again, I'd probably modify the frame as there's not a lot of room down there. I like the idea of mounting the reed valve closer to the crank, keeping the volume down. What carb are you going to use?

[holty]

i picked the rb as i know the reeds are easy to get, i was at rayspeed last weekend talking to ray and ben, they are also like a v shape so flow plenty and can cope with high flow and bhp, they are also very compact, i intend to move the housing as close to the crank as poss, i dont want to alter the frame, i have a spare frame so i can put the engine in place and adjust the intake to suit, carb is going to be a dellorto 34mm sidedraught carb, will come out on lh side of the engine mounting, will mean a cutout for the tank, i will probably just make one from scratch, rather than cutting bits off another tank.