Mileage/Reliability for an iron barrelled 225

[Mr G in NYC]

Yes please post pictures......... hopefully not 'Locked' pics
look forward to seeing that project of yours good luck .

I'm gonna fit the old scored barrel once cleaned up on a SX200
that is stock paint ........it should be a 70+ bog standard looking
SX200. Just waiting on the pipe from the ceramic coaters....to
come back and thats my winter project

[Dimitrios_231]

I plan to finish it in 2016,I'm not in a hurry.
I'm collecting parts for it the last 3-4 years.It will have (hopefully) a vast amount of original parts.
I have many other projects (not mine) in between to do.

Your piston is fecked but the barrel looks OK,a rebore and will be fine.
Good luck with all the other projects

[Dimitrios_231]

Stormy weather last night

[Dimitrios_231]

Two barrels are better than one.







Piston to bore clearance 0.1mm or 4 thou.







The deck height is 32mm which suits better the 62/116mm crank.
At BDC it will be the same as it was with the 107mm crank and standard 39mm deck height piston,using a standard base gasket.
A thick head gasket will be used to set the squish as the piston crown will protrude the top of the cylinder.





I'll start to work with the ports later this year or early next year,
I'm still waiting for the crank,I'll have it next week.

[Dimitrios_231]

This is also an option.
I can do one of the two barrels like this.

I run without problems a 2mm thick gasket (and 3.5mm packer) on the Rapido 252.43cc that I have.
The piston crown also protrudes there.I use it with a 62/110 crank.

Theoretically,
on the Kawa project.
The timing in standard form,using a standard base gasket and 2mm head gasket, will be:

EX 152.89
TR 121.57
IN 155.26

Squish 1.2 to 1.5mm

If I raise 5mm the exhaust port,I'll get 172.42
If I raise 6mm the exhaust port,I'll get 176.17

In general, I don't plan to use larger than 180 degrees of exhaust and 160 degrees of inlet.
I intend to use a 48mm clubman exhaust with a 30mm or 32mm Amal MK1 plus SX200 gearing.

[Dimitrios_231]

I'm a little confused about the exact settings used on the Rapido,
I have the data somewhere stored but I cannot find it now.
The head gasket could also be 1.5mm and the packer 2.5mm sandwiched with two standard base gaskets,
I cannot remember clearly as it was done 3-4 years ago.

[Dimitrios_231]

Υeah I know

These results are without raising the exhaust.

[Dimitrios_231]

I'll be able to talk about timing and other things when I get and fit the bloody crank
I can only assume now.
I'm really curious how this project will end.
I have ridden this untuned Autisa 200cc cylinder with standard exhaust and SH1/20 carb and it was feeling like a standard Li150.

[Dimitrios_231]

This is the Rapido at TDC

[Dimitrios_231]

Holy shit
Eden you are right.
On the previous theoretical calcs,I forgot to add the extra 2mm of the 62mm crank for TDC.It worked nice for the BDC though.
The total length will be 150mm (116+32+2) compared to the standard 146mm (107+39).4mm difference.
When I checked with the standard piston/crank the deck height was 0.5mm.
This means that I'll have 3.5mm negative deck,
I'll need a 3.5mm packer to get the piston crown level with the top of the barrel.
I calculated earlier for 1.5mm negative deck instead of 3.5mm,my mistake
This is the problem when someone tries to calculate timing without having the parts assembled.

[Adam_Winstone]

Don't let Eden convince you to raise the barrel too much though or your transfer timing will go too high. Eden does like porting that works well with a JL4, whereas, I know that you like a load more grunt.

I do agree that head gaskets are nasty though. In order to get rid of head gaskets, I normally reprofile the head with the recess that I'm looking for cut into the head. You'll need to dowel the head to the barrel so that they stay in alignment, however, you would be well advised to do that anyway with a 'floating' fat gasket.

I guess this all depends on what you want the end result to ride like. Decide what you want, then determine what port timings would deliver this, then see how best to achieve these timings.

A motor can be anything that you want it to be... it just can't be all things to all people.... make it yours

Adam

PS - I like to set my transfers first... but that's just me.

[Dimitrios_231]

Thank you for the input guys.
I'll wait for the crank first to come.
If anyone is bored and wants to play with the calculator

The distance from top of the barrel:

Trans 47.83mm
Ex 40.75mm
In 94.88mm

Piston compression height 32mm
Piston height 68mm

Crank 62/116mm

Using the same barrel with standard 58/107mm crank and a standard piston with 71mm height and 39mm compression height plus a 0.55mm standard base gasket:

- At BDC the piston was level with the bottom of exhaust port.



- At TDC it was 0.5mm bellow the top of the barrel.

[Adam_Winstone]

Adam, what you calling too high on the transfers then? If the transfer heights in the barrel are what has been quoted, running a zero deck wouldn't make them too high imo to lose grunt, they wouldn't be as high as the transfers on my cast 240 and that's got plenty of grunt

fully agree though that he should make the barrel his own by doing whatever he sees fit.

All depends where you want that grunt to be and how you intend the porting to relate to the rev range at which the pipe makes power and the gearing that you are hoping to run. What people overlook all too commonly is that in today's dyno era, where so many people can only see BHP figures, the JL4 / Fran Race pipe is quite accepted for road use, whereas it should be remembered that it is a Group IV winning 'race' pipe design. Sure, it is a great pipe as far as BHP is concerned (actually a very good pipe for grunt as far as race pipes are concerned!) but my iron motor with 185 degrees exhaust port timing will happily rev over 10K rpm through the gears and return very high BHP figures... BUT it doesn't ride as well as when it is fitted with a JL3, even though it loses 5 BHP!

If you return to the feature that Scootering ran on the RS250, calling it one of the most memorable and fasted bikes that they had ever had the joy to test ride, the BHP figures are not anything like as the high BHP figures that many of today's 'fashion' bikes are putting out... yet these don't get a look in when it comes to their list of memorable bikes.

The fitment of 110mm rods and/or the base machining of MB and Taff's popular TS1tunes, to widen the spread of power, is designed to lower the standard TS1 transfers to bring them under 130 duration. These tunes did not become the UK's most popular road tunes by chance, the reduced transfer timing (combined with some raising and widening of the exhaust, along with the increased lead) returned a much better spread of power for road use. SURE, multi-transfer reed motors are not the same as 2 transfer iron barrels but I've had vast improvements in gear pulling ability and lower rev touring torque from reducing the 130 transfer duration of Rapido Race barrels, again playing with exhaust ports at the same time. Keeping transfer durations to 130 or less on a long-stroke motor is not that easy, hence why a JL4/Fran Race suits your iron motor so well... but fit a low RPM pipe to your iron motor and I'm pretty sure that you would lose the match of porting and pipe rev range and the bike would not run anything like it does on the 4. Your iron motor is basically running along similar lines to an 80s/90s race motor, which will not suit the riding style of many other road riders.

Don't get me wrong, high RPM revvy motors can be used on the road (providing you don't mind having the best of clutches and cranks, and replacing them every so often) and be lots of fun (if that's how you ride) but I'm more interested in looking at a dyno graph between 5 and 8K than I am between 7 and 9K. The RS250 was last seen running a JL3/Fran Road and that suggests that it does not need, or want, to run a JL4 at higher revs to make power. As they say about the JL4 in Scooter Centre's informative catalogue, the JL4 can transform any mundane motor into a high BHP motor This is more the result of the pipe than the motor

Adam

PS - I still love you though, even if you do abuse Innocenti's finest!

[Steve J]

On the subject of reliability.... I bought an Avanti 70mm piston last year, with the intention of doing a 225 conversion on my otherwise standard 'Stage 4' 200 - all very straightforward. I also have an unused barrel for an Indian Lambro 200 (courtesy of MB a few years back), which has the strange small block spacing on the inlet port, which I believe I can sort out/remachine to fit a sensible inlet manifold. The one possible advantage is that the Lambro barrel has fully enclosed cylinder stud holes (just like on alloy barrels), which may give better rigidity and more even heat transfer with larger bores. Before I start carving out ports, making adaptor plates for the inlet, etc. - has anyone attempted to use this type of barrel for a 225 (or larger), or is the whole thing just a crazy idea on my part?

[Adam_Winstone]

You need to see what the port timings are like as the Italian Lambro 200 barrels that I've played with (2 x imports fitted with Lambro 200 barrels with spigot machined down and stud holes reworked for 150 casing use) have had inlet durations over a standard TV200 barrel. This duration will change a little when bored out to 225, however, you'll want to consider your options and what port timings you wan to end up with.

Also, whilst the Italian Lambro 200 inlet has very long timing, the port is very thin (bottom edge to top edge) and you may need to remove a lot of metal from the top edge to give the port a decent area.

In standard port configuration these Lambro 200 barrels really pull (carry as many bags of spuds as you like... at 30mph) but do not rev, and I really mean do not rev! Even with a free revving pipe, the porting of the Italian barrel just doesn't allow the motor to rev and you get so far up the rev range, totally 'hit a wall', and must change up. The ride of these, unless the porting is modified is really nasty.

I've not seen the SIL Lambro barrels but, if the SIL 200 barrels (150 and 200) are anything to go by, don't expect ports to be cast too well or for them to be symetrical through their length, which really shows up when they are bored out beyond their intended cc. Note that working transfers throughout their entire length is not very easy.

Who knows, these SIL Lambro barrels might be a decent starting point for a 225 conversion but you'll need to examine the barrel once over-bored and then have to do a fair bit of porting to give a decent end result.

Let us know how you get on

Adam

[Adam_Winstone]

Did you miss...?

"Sure, it is a great pipe as far as BHP is concerned (actually a very good pipe for grunt as far as race pipes are concerned!)"


The JL4 is a very good pipe but it does let motors rev into what should be considered the 'red line' range for Lambretta motors/cranks.

I totally agree about the balance of port durations, rather than looking at durations individually, however, that doesn't mean that you shouldn't look at them ALL together. Typically, certain port durations work best at certain RPM ranges, and pipes work best at certain RPM ranges too. What is nasty is when tuning and pipes (and gearing combo) are out of synch and one strangles t'other. There is nothing like just getting into the power and finding that your pipe limits the barrel or vice versa


"How then do you explain my cast 240 making max power of 27bhp at only a tad over 6600 rpm "... a dyno can tell you anything that you want it to... and let's face it, your bike is pretty much a 'dyno pony' and never does any serious miles!

Adam

PS: Yeah Baby, but that's because I treat you right!

[Dimitrios_231]

Crank arrived,
I'll need to machine the crankcase a little more closer to the cylinder base.
I'm also waiting for a wider Wiseco little end needle bearing.



One standard gasket


BDC


TDC


One gasket plus a 2mm packer


BDC


TDC



I'll set the squish first.
Then decide between base and head gaskets to set the transfer timing.I intend to use a head gasket.
Then I'll lower the bottom of transfers and exhaust.
Then I'll raise the exhaust.

I'll be off my place for two weeks,I'll report later.

[Adam_Winstone]

Looking good

[Dimitrios_231]

I had used this crankcase with a Rapido 225,5-6 years ago.
I had opened the transfers to match it.
I'll open/match the cylinder transfer entries with the cranckcase.
I'll round the thin cylinder walls,and cut them even.
Then I'll check if the piston skirt clears or not the transfers.
If the skirt covers any port,I'll cut the skirt.
I've already checked that at BDC the skirt stays clear from the crankcase.
Another positive is that the piston rings are not exposed on the inlet at BDC.
I have a felling that I'll end up somewhere close to 1.5mm head gasket and a 2mm or 1.5mm base packer, sandwiched with two base gaskets.

On the top pic (with one 0.55mm gasket only),without tightening the cylinder as I didn't have time for accurate measurements,I had 2.85mm negative deck.

[Adam_Winstone]

"........ yes Adam you fanny... its not been on a dyno for over 18 months...", that's done it, now I'm in trouble

I'm in trouble because my wife asked me to do the washing up of the dinner pots and pans, then I start laughing at your comment, which she mistakes for me laughing at her suggestion, barks something at me, storms off and slams the door! Eden, that is so your fault!

Dimitrios,

Sounds like your plan is coming together.

Adam