LCGB Forums

Hello all

I've been talking to a couple of people just lately about the Rapido kit and what people are experiencing with their setups.

I know i'm probably going over "well discussed" land here, but I (and i'm sure a few other people) would be interested in anyone posting their results with Rapidos.. in 200/225 classic and race form.

I'm looking for engine spec and accurate cruising/top speeds. I'm thinking GPS or rev counter derived results rather than dodgy speedo results.

It seems to me that if bolted on without any fettling, the classic has grunt, but then seems to just come to a halt at between 60 and 65mph. I've tried various carbs, pipes and gearing and i've achieved pretty much the same results.

Is it a mis match of port timings? Port shaping? Something else far more technical????

I'd appreciate any input. As I said earlier, I apologise if we're going over old ground, but i'd like to try and get to the bottom of the problem that i'm experiencing.

Any clever bods want to give us a few hints????

Cheers

Jon

I havnt had my GP out at full speed with the GPS only clocked by my mates... but I think its well capable of 70 on my GPS, I will be out on it after work I hope on Saturday.... if I get it up to speed I will post a Genuine GPS speed... I cant see mine as its kept in my pocket (no mount) but it holds a memory of the fastest recorded speed....

Anyone else out on theres with GPS..??

Rapido 200, 65.5 racetour piston, widened exhaust port, fettled transfers, 1.2mm squish, 24ml Mikuni- 27.5 pilot, std needle middle clip, 135 main - through std airbox with camlam fast flo filter, Camlam/Sito Ancilotti, GP 200 gearing, 71.8 mph (Garmin Quest) into a slight headwind on a flat road. Cruise is 58-62, pulls well up hills to a GPS 51mph.

I will add a post soon with a GPS speed... I just never got out on the Lambretta last week, went out on my T-Max instead.... GPS on the T-Max showed a little over 60mph...

Rusty-Bretta 71.8mph can't get nowhere near that

Rapido Classic 200 with fettled exhaust port, Mahele 2 ring piston, TM24 carb on foam filter-175 main-15 pilot-5N13 clip at top, 42mm KBA clubman, Li150 box on 16/47 sprockets. 60mph tops

my rapido race 200 with a 48mm reverse cone clubman gp200 gearing and a pwk carb did a gps"ed 73mph on our local "mad mile"---but--- it never felt like it was set up properly,it took me to sweden and back with out a problem--now up for sale if your interested

am i missing the purpose of a rapido kit here?? i have a gp200 with 19 sprocket, 30 mm dell'orto with 127 main jet and a sterling rice eater stainless sh*t pipe and my gp with its UNTUNED STANDARD tv200 barrell + INDIAN PISTON pulls 78 gps and cruises at 68/70 gps. so looks like cast iron is fast iron .my set up isnt high tech but if the best id got out of a kit called "rapido" was less than that on gp gearing i'd be a little less calm and patient than you. i hope you didnt waste money on a hydraulic disc brake when it sounds like you could stop it with your feet! we also had a nightmare getting a mugello 225 kit to outperform my standard sx200, we bought that cus a guy on a rally reckoned his did 80!! yeah 80 kph!! ( see my thread trouble with mugello 225)im beginning to wonder if these fancy named kits have hotter names than the technology that went into them...........

I have also tried my old spanish 200 iron barrel only to hit 60mph tops & thats it just like the Rapido:(

The beauty of Rapido is in the cooling and transfer area. With the classic you can set the port timings to match Carb and Exhaust as you have a bit more scope to play with. My whole set up was based around the 24ml and the Clubman style pipe with a rev out at 7.5k. The big part is in maintaining the performance when it gets hot. All iron barrels loose a lot of performance when hot, iron/alloy- a bit less Alloy retain more performance and LC retains even more. We found this on the recent 6hr endurance, the LC RB was a wonder, it did loose some power, but not as half as much as I expected compared to previous TS1 runs. Saying that my mate has always sworn by big carbs and expansion exhausts on Std Barrels, they go well, but he is not a splash and dasher like me on long runs. Lambretta motors are pretty well under cooled. Anything that aids that is a boon. My set up is based on long runs with good fuel consumption, I no longer want the high sixties cruise from my TS1 (it now sports a clubman and reduced port timings) and this Rapido fits the bill; my big disappointment is in the quality of the liner. Again, showing wear even just after running it in. I will reline it with the same port timings and hopefully this time will be able to leave it together for more than the 6.5k miles this time. I like 60mph on the road with good fuel consumption, and the fatigue on the combined componenets is minimal, I probably can get more top end with Pipes and port timings, but I suit it and it suits me, we are a happy team on the Carreteras de Espana

you have struck gold there-- if you could put your finger on why yours is so much quicker and pass it on it makes all these kits superflous 78 beats 50 % of the ts1"s around

Ralph saxelby spent a week building it for me.I was amazed by my return to iron too.I will be dynoing it when i get a chance just for a jolly but i suspect its around 14 or 15 horses , dont know how much power a Rapido is knocking out but i guess its more ""speed = rolling resistance x frontal area x power""somebody was telling me at cleethorpes hmmm ive stripped off all surplus bolt ons to minimise drap, snett seat and weigh about 12 stone, 78 acheived on m1 just after Tibshelf services heading north. my feeling is a well set up engine will perform well. Id like to try bolting a Rapido barrel onto my engine and try the same run but its all more complex than that isnt it. i wish i just owned a p200e and spent my time on the vespa site talking about what colour indicator lenses i could fit for easter egg runs.

yes i reckon losing 4-5 stone would be the best "tuning" i could carry out when you say its standard did ralph not do any porting etc--one of my mates was dynod at 19bhp but doesnt get 78mph.i also think you just get lucky sometimes when you have everything set up right and strike lucky with a barrell and piston made to the correct tolerances

Abolutely agree its the setup that makes the engine. Im interested to see what the fastest speed a Rapido has acheived now!! considering a good italian GP 150 with 22 mm carb will do over 60 this is interesting as the Dyno gives indications of all the torks and horses but the motorway is where id be interested in the top speed. some of the guys round here have been buying these fancy digital speedos and on the cleethorpes campsite i was showed the stored maximum speed on the m180 of 73 for an untuned mugello 200 with franspeed pipe and 30mm dell'orto so the Rapido should be quicker?? i think this thread and others are crucial for people spending hard earned dollars so they can make the right choice of kit and learn from other peoples experience in testing them.There are so many alloy barrels out there now !!!!

Lost me on that photo...

The biggest difference to a 2 stroke is made with a pipe. Belfast Uni had lots of development on 2 stroke stuff and they concentrated on the pipes to make the motors work. I stuck to box pipes as I like the look and take the severe loss of power on the chin. For me, its in the reliability and the consistent performance over my Iron barrel. I had considered putting the racetour in the Stg IV as I was well pleased with the performance of it, but not happy about the piston and its design limits, not to mention the iron cooling. So many variables are involved in motors, trying to replicate them and get a comparable base from which to raise a plausible comparison would be very time consuming. But my direct barrel and piston swap between a Stg IV and the classic Rapido showed a reduction in top end, but I would fair a better long term motor (if the liner holds out), hence back to the Rapido. I am no longer a thrasher and prefer to travel, but my mind is more at ease with the knowledge of what helps motors survive (through mine and others misfortunes) being applied to my motor and riding style. I had considered the Mugello, but was put off by its noted limitations. My next test ride is the 1000k ride in 42 deg heat... lets see if I eat my words....