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Re: Rimini 5 speed box

Posted: Fri May 04, 2012 1:55 pm
by soulsurfer
There will also be choices in 1st & 5th gears ;-)

Re: Rimini 5 speed box

Posted: Fri May 04, 2012 2:28 pm
by GP Kevo

Re: Rimini 5 speed box

Posted: Fri May 04, 2012 2:37 pm
by alcoholic maniacs sc
Muttley McLadd wrote:
soulsurfer wrote:I think a 5 speed box will improve many TS1/RB type motors into something many people want. It'll make it much more tractable and even out any gear step/rpm issues. A great innovation IMO.
Or step over the untractable nature of the engine.
A tractable engine is the one that can pull the four speed box without dropping out of the power.
agreed, if i couldnt get my torque spread smooth over four gears i'd work at it til i did not fit a 5 speed box, my bike doesnt labour in gear because i change it to the correct gear. a bit like variotronics, can't tune your engine correctly,dont worry a variotronic will hide the problem.sorry for being so negative, the credit crunch is biting my balls a little harder these days.

Re: Rimini 5 speed box

Posted: Fri May 04, 2012 2:50 pm
by soulsurfer
I guess we should all downgrade our cars and bikes to 4 speed then, what do these Jap and German manufacturers know anyway :roll:

Re: Rimini 5 speed box

Posted: Fri May 04, 2012 3:20 pm
by GP Kevo
With a 4-speed gearbox tuning is limited to what your gearbox will allow. Try riding a 3 speed scooter, tuning is even more limited. The same was true of old 60's American cars. Most Chevy's came with a 2-speed "Powerglide" transmission and required low revving, high torque engines. Even then, the transmission (an automatic) required a lot of clutch slippage between the two gears. As the muscle car wars upped the performance stakes, car makers responded with engines featuring high lift camshafts that were revving higher and so required moving up to 4-speed transmissions. The same is true today with cars like the Corvette, with 6-speed manual transmissions, or with modern sportbikes that feature 6 speed transmissions. These are 4 stroke examples but the same applies to 2 strokes. The Aprilia RS250 has a 6-speed gearbox to suit the tuning of the Suzuki RGV barrels.

We can go a step further: Modern twist and go scooters feature CVT transmissions that offer continuously variable gearing. The engine can be tuned to a very narrow power band and the transmission set up to always offer the best gear ratio no matter what the speed of the bike. That's how wickedly tuned 50 and 70 cc Piaggio Zips are able to keep up with and often win against much larger displacement Lambrettas. A 4-speed Lambretta tuned like a 70 cc racing scooter would be unrideable. But a 5-speed Lambretta would allow more tuning and be faster round the track, as long as the transmission doesn't break. The only reason 5-speed Lambretta transmissions haven't taken off is because they have been weak and broke when used in performance engines. If RLC can market a durable and strong transmission with a well chosen gear ratio spread at the right price, they shouldn't worry about them not selling.

Re: Rimini 5 speed box

Posted: Fri May 04, 2012 5:08 pm
by alcoholic maniacs sc
yeah well you can't argue with logic so Riminis gearbox will probably be a must have , its took me weeks of indecision to finally decide to ditch my analogue wobbly CEV speedo and get a SIP digital one. like losing a faithfull but lying old friend who had constantly entertained me on the way to rallies with tales of post 80mph speeds through roundabouts. i can't say i want the reality shock of my actual top speeds. i had a 1200cc motorbike with 5 speed box last year and only thrashed it around with the first three gears, maybe hoodlum riders would likethe surplus weight of the other two gears removing in the quest to get better acceleration out of the first three, esxcept the sad truth is i sold it because it made my neck and back ache.I remain unconvinced that a five speed gearbox on a Lambretta is needed when thrashing a two stroke is so much fun. theyre going to outlaw them soon anyway to make way for the sanitised world of 4 strokers and theyre well spread out gear ratios, i suppose the civilised 5 speed is a stepping stone to life with the LML 200 as your rally ride. :baddevil:

Re: Rimini 5 speed box

Posted: Sat May 05, 2012 8:58 am
by mick1
I wonder how good and durable the "low cost" Indian version will be....and how quickly they get it into production for sale on *-bay ?

Re: Rimini 5 speed box

Posted: Sat May 05, 2012 9:25 am
by soulsurfer
Worth a read...
http://lambrettaspares.com/info/lambret ... ne+79.html

"As we go to press there are a few dealers working on some cheaper versions of the 5 speed gearbox! Is it needed? Well it depends on how you look at it and your engine. When you ride a real Lambretta engine and have the benefit of a 5 speed you wouldn't go back to a 4 speed........ it really could be the future of Lambretta engines."

Re: Rimini 5 speed box

Posted: Sat May 05, 2012 11:16 am
by Treeman
Excuse my lack of knowledge when it comes to gear ratios (and gear boxes) etc, but a 5 speed box (in simple terms) could allow if set correctly, you to move from one gear to the next at lower RPM (than a 4 speed box) still maintaining a continued smooth (and smaller movements) up the gears whilst increasing speed. Meaning you could achieve say, 70 mph in 5th at a lower rpm than a 4 speed box? Could you also increase the top speed using a 5 speed box? Thanks.

Re: Rimini 5 speed box

Posted: Thu Jul 05, 2012 8:08 am
by Avantone
Already to go in the next version of the visualiser - just need the ratios confirmed............

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