small block engine upgrade options ?

[shocky]

Just make sure that the rest of the motor isn't worn out. If your bike chucks out say, 8hp and you put a basic kit on it that makes it put out 10hp,then that's a 20% increase in power,.so just be prepared.

25% you mean

[johnny LIS150]

yes good advice speedy I have only just got the scoot so I can only guess at the wear and damage at the moment

The whole bike will need a complete mechanical overhaul top to bottom but until I strip and check everything I have no idea what I'll find .

One thing is for certain I would definitely replace the piston and rings and wrist pin anyway as a matter of course with a top end strip down and the cylinder would need to be bored and honed so it makes sense to buy a complete bolt on cylinder kit which is cheaper and easier and will give some useful power boost to boot !

[johnny LIS150]

Just make sure that the rest of the motor isn't worn out. If your bike chucks out say, 8hp and you put a basic kit on it that makes it put out 10hp,then that's a 20% increase in power,.so just be prepared.

25% you mean

hey I've just gained a 5% power boost and I haven't done a thing lol

[speedy]

Just make sure that the rest of the motor isn't worn out. If your bike chucks out say, 8hp and you put a basic kit on it that makes it put out 10hp,then that's a 20% increase in power,.so just be prepared.

25% you mean

Bugger,you got me ,mathematics were not my strong point. I find two thirds of my brain are working and the other quarter isn.t

[johnny LIS150]

thanks speedy I needed a good larf.
I'm painting the kitchen at the moment before swmbo's Mother comes down in 2 weeks time .

[mawso]

Just some opInions, everyone has their own, but good value and an improvement on your 150 might be something like AF Rayspeed 175 (in iron or alloy with iron liner), they even sell 175 conversion pistons for bored out 150's so you could even just have your barrel ported to suit. A 22mm standard type lambretta carb or upto a 25mm PHBL (to run through air box and hose), along with a 42mm AF or KBR clubman (standard looks) or a Fresco for bit more oomph all round. That would all come in around or maybe under the price of an RT kit alone. But as mentioned before a GT kit for me too over the rest if I was choosing again. I'd seen that Ian Frankland did a photo thread on Facebook of a Gori kit he had been sent to work on for a customer. I don't think he was too impressed with how it arrived in standard form and had to do a lot of work on it, just to make it right and useable. That said it could have been just one bad one, you could ask him he's on here and very helpful. I don't think an engine with decent bearings and a decent GP crank will get over stressed at 60 - 65 mph, there might not be a lot left in a 175 above 60, but bearings and crank should be ok at least.
In our club there's an Imola, Mugello (now changed to RB20) a GT185, a 175 Iron kit and my Suzuki 185. The GT uses the least fuel by far. The Imola is nothing special until he's really revving. My Suzuki kit is 17 years old now and performs well. The design must be over 30 years old...but still hard to beat today if set up right though.

[drunkmunkey6969]

I'd agree with Stu (Mawso) on this.....the request was for simple and cheap for a little more grunt. A 175 kit, maybe light porting to tidy it up, 25mm Delly and a cheap pipe.....KBR etc? Keep it cheap, keep it simple.....that was the brief on this one

[johnny LIS150]

thanks guys . This is all new to me and a bit of a minefield to be honest. Folk have been tuning these things for 50+ years so there are lots of solutions out there and its difficult to sort through for a noob like me. I remember meeting some old school mates at Roys of Hornchurch back in 1967 and as we were leaving one of the Hornchurch lads that had a lambo chop went past us like we were standing still . he had a job keeping the front wheel on the road !

Why are the 186cc kits so popular ? do they have better tuning possibilities that a 150 bored to 200cc ?

[johnny LIS150]

In our club there's an Imola, Mugello (now changed to RB20) a GT185, a 175 Iron kit and my Suzuki 185. The GT uses the least fuel by far. The Imola is nothing special until he's really revving. My Suzuki kit is 17 years old now and performs well. The design must be over 30 years old...but still hard to beat today if set up right though.

whats a Suzuki kit comprise of Stu ?
Also talking about gearboxes would my 64 LIS150 have a 'pacemaker' gearbox fitted as standard ? or would it just have standard series 3 ratios ?

[mawso]

A Suzuki kit is basically using an ER185 trials bike piston in your barrel. Although that said the cylinder head needs reprofiling to match the piston dome. If using a standard GP 107mm con rod then the barrel needs topping and tailing or use an RD 400 or TV length conrod and keep barrel standard length. It would be easier to just get a 175 kit off the shelf from a dealer that's been checked over and have them or someone from this forum do a bit of extra work matching inlets and exhaust and maybe some slight porting. Have a look on AF website. You can get a 175 barrel for £50 right upto a factory Stage 4 alloy 175 for under £200.00. eBay alloy 185's are cheaper but need work and not sure will give much better performance and the liners are thin, often badly fitted, not round and wear quickly. I'm not an expert I'm just offering an opinion which others might not agree with : )