lambretta 290 rotax

[dickie]

What's the theory behind nitride? I thought it was used to reduce static friction.

[Adam_Winstone]

Nice work Holty.

Your piston reminds me of the 72mm Wiseco that I have mated to a 64-65mm stroke crank in my Mugello, which has served me well.

Keep up the good work.

Adam

[peter357bikes]

reading with massive interest...the beast

[holty]

What's the theory behind nitride? I thought it was used to reduce static friction.

i belive that nitriding is a hardening process that works on the outside, makes it stronger on the outside, but the inside retains the flexibility, the idea being the crank pin will not split the crank web when pressed home, i good tight pin helps to prevent it twisting, as will the wider webs.

[holty]

made some progress, got my case back and ive machined it to accept the cylinder, here what it looks like
[url][url=https://flic.kr/p/WqMRoQ][/url]IMG_0172_zpsy4i54a3g by stephen holt, on Flickr[/url]
[url][url=https://flic.kr/p/Wur4jk][/url]IMG_0171_zpsdxhwqypq by stephen holt, on Flickr[/url]
[url][url=https://flic.kr/p/Wm26fm][/url]IMG_0170_zpsrrqf2gpm by stephen holt, on Flickr[/url]

[Warkton Tornado No.1]

It's a great project. I'm sure it will work well but no doubt you are ahead of any problems with the drive train...

I wonder what gearbox you intend to use.

I believe that of all the original types that the GT/TV 200 is the strongest.

Personally, I've had the specially manufactured gears brake with use in only a Group Four motor without being subjected to real race abuse, so I dread to think how they would handle the likely torque you should predict.

If I can suggest it, don't skimp on the clutch, particularly in ensuring that the clutch clears well, without any element of drag as that really adds more likelihood of breakage.

My apologies if you are ahead of me here, but it would be a shame to not be able to utilise the performance you should gain.

[holty]

It's a great project. I'm sure it will work well but no doubt you are ahead of any problems with the drive train...

I wonder what gearbox you intend to use.

I believe that of all the original types that the GT/TV 200 is the strongest.

Personally, I've had the specially manufactured gears brake with use in only a Group Four motor without being subjected to real race abuse, so I dread to think how they would handle the likely torque you should predict.

If I can suggest it, don't skimp on the clutch, particularly in ensuring that the clutch clears well, without any element of drag as that really adds more likelihood of breakage.

My apologies if you are ahead of me here, but it would be a shame to not be able to utilise the performance you should gain.

all very good points, i already have an af close ratio box that im going to use, clutch wise i am going down the af route, i do see where your coming from power wise, and how things might break, hence why i havent tuned the cylinder, i will have to ride it with quite a bit of care i think, heres some pics of the crank i collected on wednesday from martin at chiselspeed, larger diameter webs and wider too, and 64mm stroke, a nice bit of kit.
[urlIMG_0178_zpsqfqitchr by stephen holt, on Flickr][/url]
[urlIMG_0179_zpsimehkjsr by stephen holt, on Flickr][/url]
[url][url=https://flic.kr/p/VPioQ9][/url]IMG_0177_zpsvktc46bl by stephen holt, on Flickr[/url]

[Warkton Tornado No.1]

That crankshaft looks the business.

Did Martin build it from commercially available webs? If so, who makes them, please?

I put a bit more thought into the clutch, or @ least a way of limiting the shock to the gearbox. It would mean converting a motorcycle clutch though, but very 'do-able'

However, musn't put myself in the position of some claiming 'Hijack!'

This project really deserves to suceed

[holty]

martin had the webs made to his spec, the same webs he uses on his race scooter, he has another pair in stock, ring him if your intrested, i was recomended this crank by someone who has used them before and has a second one he liked it so much, your idea of a cush drive is not a bad one, but will take a bit of doing, a lot of motorcycles use rubber discs between clutch basket inner and outer as a cush drive

[Wack]

It will cost but I think Casa are bringing out a big cush drive clutch to use with their special side casing which I think also fits standard casings. Also you will find that a Ser 2 shock is longer and will give less clearance at the top end to frame, either a Yamaha R1 or similar may help.

[holty]

It will cost but I think Casa are bringing out a big cush drive clutch to use with their special side casing which I think also fits standard casings. Also you will find that a Ser 2 shock is longer and will give less clearance at the top end to frame, either a Yamaha R1 or similar may help.

your right about the shocker, i tried a series 1 shock and it gives me more clearance around the inlet manifold, but the head is quite close to the frame, it will be even closer when ive got a packer under the barrel, i might alter the head a bit, thats a job to tackle later, just waiting for my casing to come back from the welders, its having a few more bits welded.

[Warkton Tornado No.1]

Post by Wack » Fri Dec 09, 2016 7:18 pm

It will cost but I think Casa are bringing out a big cush drive clutch to use with their special side casing which I think also fits standard casings

Well, we’ve got used to ‘chequebook’ customising & I suppose ‘chequebook’ tuning is already here.

However, this here project is an example of an owner doing as much as he can himself, which I think is more accessible & affordable. It's also very interesting!

I don’t want to stray off Topic, but there are complete, well proven motorcycle clutches with built in cush drive that can be adopted with our resourceful attitude & ability.

Hopefully, the next one I do will prove the point.

[holty]

im pleased your impressed with the diy , low cost job, its a bit harder doing it this way, and takes longer, but much more satisfaction looking at the end product knowing its all your own work, i will look forward to having a look at your cush drive
holty

[LateAgain]

Quality stuff.

[bike grim]

Very ambitious project. Have you seen the latest Gran Turismo GT300 casings offer from Rich Taylor along the same lines? Posted these pics yesterday, there's more on FB.

[holty]

Very ambitious project. Have you seen the latest Gran Turismo GT300 casings offer from Rich Taylor along the same lines? Posted these pics yesterday, there's more on FB.

yes i know he is building one, i tried to get him to sell me a casing but he wouldnt sell me one, im happy with where mine is going, its just a little frustrating waiting for more welding on the case, will be worth it when its done, i can see he has similar issues to me, head close to frame, i might cut a notch in my head, and not much room for the inlet, i guess his will be done before mine, but will be worth the wait, plus ive the satisfaction of building it myself.

[Dazts1]

Very impressive work. Definitely a step in the correct direction.

But crankcase induction has been around for a few year now. This motor was 1st done in 1991. It's been in a few scoots over the years in a few different strokes , cc's etc. It's currently about to go through another upgrade on the ts cylinder but I have considered one of these cylinders. Interested to see how it comes along.






Very envious

[holty]

some good work gone into that motor, whats the upgrade your doing to the ts1 i can see its got an extra port running from the reedvalve to the boost port, im doing the same with mine,
heres a couple of pics, ive got my mag housing spacer, circlip and seal.
[urlIMG_0190_zpscjsyhsic by stephen holt, on Flickr][/url]
[urlIMG_0245_zpsg6hobc4j by stephen holt, on Flickr][/url]

[holty]

got my casing back from the welders, can start doing some of the serious work now, ive done some repairs to the gearbox endplate studs and dowels, just getting it set up on my lathe now to machine it out for the crank, heres some pics
[urlIMG_0617_zps1ucdloih by stephen holt, on Flickr][/url]
[url][url=https://flic.kr/p/VPix6C][/url]IMG_0618_zpsxsv20sjk by stephen holt, on Flickr[/url]
[url][url=https://flic.kr/p/VPiz2m][/url]IMG_0619_zpsnvkjaedq by stephen holt, on Flickr[/url]

[Knowledge]

What's all this about Holty?