Engine size/power

[Bugsy_malone 666]

Ok so I am due to pick myself up a chinese engine of some sort its a 165F engine, looking on the internet its about 200cc and 3hp, so the question I have is would this work ok in a bike?

I have a little 250cc kawazaki Z250 from 1980, needs a major rebuild but basically its a bike frame with documents which I planned to rebuild 10 years ago, but a fairly small light bike and was 33bhp originally.

obviously diesels tend to be a bit different when it comes to actual power output compaired to petrols so a 33bhp engine is probably about 10bhp in diesel terms.

Any advice (especially now I bought an engine lol)

[alexanderfoti]

I have a superdream that originally had a 170f in it, around 5bhp, and it was SLOWWWW, IT would top out at 38mph, and for anything other than town driving was dangerous!

I now have the 186f 400cc in it, and its a dramatic improvement, its currently geared for 50-55 but it could hit 60 no problems.

So, to answer your question, it would work in a bike, but it depends on what you want to do with it and how you want to ride it

[Stuart]

Be prepared to do some work on the engine as these clones are not that reliable. Buy cheap, buy twice goes the saying. I'd rather see builders getting genuine old Yanmars & lavishing some TLC on those personally.

[Bugsy_malone 666]

Well basically I bought this unit for £65, its never been run apparently and was made in 1987! Still turns over etc so I am going to investigate the unit to make sure its ok.

I know with normal engines you can turn up the fueling a little and give it forced induction and get more power out of it, I figured maybe with a free flow exhaust it might be ok, I wondered how you actually give a 200cc engine forced induction other than a big fan lol.

with the 170f, how did you gear it to the rear wheel, I'd be interested in some info/pics if you have any

[alexanderfoti]

Of coursre, It was purchased from Tim on here before I converted it to a 400 cc (As i thought that a whole project would be too much for me as a first one) Have a look at fotifixes.com under the Diesel bike project category.

[Bugsy_malone 666]

I had a quick look but it appears the website is a little unreliable! I could only see some pictures on there of the finished product.

Interesting the mention of the supercharger idea!

according to the internet the 165F is supposed to be something like 199cc so I figured 200cc is 200cc pretty much, its all a case of making it work the best I can

The next problem is the fact the 165F I have doesnt have convensional input/output shafts!

[Stuart]

I feel I have to throw the reliability issue into the ring once in a while just to make guys aware but yes, £65 is a very good price!

[alexanderfoti]

Sorry about that, I have been having trouble with my webserver recently, all fixed now, and all picture accessible

What is the output shaft of your engine? Taperlock bushes and sprockets can be made to work with a variety of engine configurations.

I had to turn my taperlock bush from 25 to 26mm if I remember, as they didn't make a bush in my size, a local metal shop did this for me for 5 pounds.

[Bugsy_malone 666]

This is what my engine will look like (different colour mind!)





So basically if you look at the first picture there is a shaft, but thats for the handle start, if you look at the second picture on the flywheel you will see in the centre there are 3 evenly spaced mounting bolt, thats where you can bolt an output too, looks like this apparently:



I can probably get an engineering shop to make me up something to mount other things too if need be.

[alexanderfoti]

That is pretty old school looking! Is it water cooled?

[alexanderfoti]

The adapter you speak of can be seen in this video :

http://www.youtube.com/watch?v=qn63muGNd8I

[Bugsy_malone 666]

That is pretty old school looking! Is it water cooled?

The one in the video is a watercooled one which is a bit strange, I think its got a hopper type cooling or something where ase the one I am getting is aircooled.

I'll have to work out an adaptor, but first I need to work out a clutch!

[alexanderfoti]

Aha fair enough.

Have a look on ebay for villiers or enfield boxes, the villers are a bit more compact (and is the one im using on mine), the enfield is a bit bigger, and also has lots of aftermarket parts for them.

[Bugsy_malone 666]

Funny thing is you mentioned about this and I found one on ebay finding a 3 speed version. What I wasn't sure about is orientation of mounting as when the are installed with a villiers engine the sit tall and slim, the way I want to install would be wide and low if that makes sense as I think my engine may have to sit on top of the gearbox. The one I have found is local to me whrich is useful but other bidders may out price me.

[alexanderfoti]

I see what you mean, A CVT transmission may be use full for you then, as they are a bit more versatile with the way they can be installed.

[Bugsy_malone 666]

I did wonder where you can get those cvt transmissions and if it would be any good with something so small engine wise, I did wonder if I might need proper gear set to make it work anygood.

[Bugsy_malone 666]

Well I got the creature home, considering it was made in 1987 its not a bad looking unit! its identical to the blue ones in my pics I posted earlier, only mine is silver and its made by 'phenix' It even came with original tool kit in a little metal box that contained the starting handle, original instructions (which are like a mini workshop manual and show you how everything goes together on the engine in both chinese and english!) and also lots of little spares, including main shaft oil seal, rings and a headgasket! Pretty comprehensive for a £65 engine!

Ok so I got the beast running, which considering it was dry of oil and fuel took a bit of doing! Little tiny bit noisy but I think it is going to take a little time for the oil to be flung round and reach everywhere, had it idling for about a minute on some red diesel I had knocking about.

The one main issue is I think the engine kind of runs the wrong direction for the project - kind of. If you look at the the picture of the other engine I posted, you'd think air cleaner and exhaust to the front of the bike, flywheel to the middle of bike (well thats what I was thinking anyway) but if you do that the flywheel would actually spin towards the back of the bike! Conventionally if you had a gear to gear situation this would be ok, however because I need to look at CVT drives this may be a problem. on the other side of the engine you only have the crank start handle output shaft, which is connected to the cam gear (with some sort of disengage mech) so you can use that.

So then the option is to have the engine the other way round so that the flywheel is on the left side of the bike nearer the front wheel and then aircleaner/exhaust near the back.

Now aside from orientation/fitment issues it doesnt seem like a bad little engine, might not be ideal but its a starting point, seems to rev up with thunder when you pull the throttle set thing open ( I didnt do it too much as I need to look over and run the engine a bit first to bed it in, its old but new!)

How do you get more power out of a diesel though? on a car you dump a turbo on it, which helps a little with power but acceleration still isnt great unless you alter the fuel advance system, with this little engine its pretty dam basic so fuel mods are 0 however I suspect some form of forced induction might work which brings me onto the next question:


How do you forcefully feed air into an engine this small? Most turbos arent likely to be big enough for the application and also this engine is only splash lubricated so theres no way to lube the turbo unless you ran a separate oil system for the turbo. So I was wondering about some sort of super charger idea.

the thing I wasnt sure on was where to start. Traditionally superchargers tend to be for something of a reasonable size, not a 200cc Chinese diesel! Then I thought what could I do to force air in? Being from the world of aircooled vws and earlier watercooled vws (diesel and otherwise) I know of alsorts of VAG parts and I was thinking, this engine doesnt have a charging system so theres the option to maybe kill 2 birds with one stone. On beetles you have a big old fan on a dynamo (or alternator but I doubt the bike needs it) and thought that the vw fan kicks out shed loads of air, if that was ducted into an airfilter chamber(a sealed one) would it possible pressurize enough to actually sort of force feed air to the engine like a primitive supercharger? On a late vw camper with the 1.7 - 2litre engines they have an alternator with a fan on the front of it which is used for blowing air through the heating system, I thought equally this may also work.

I am open to suggestions on this, but I figure it cant be that much of a diar engine its 200cc and villiers petrol engines of the 50s or the same cc were about the same bhp!

[alexanderfoti]

I have an AMR 500 and and AMR 300, the 500 would probably be too big for this but the 300 slightly underdriven would be perfect. The issue is, you probably wont be able to get that much more power out of it, assuming it puts out 6bhp now, and you want to get 10bhp, thats 40% increase in power, all the bearings etc probably wont be able to take the increase in power.

If you have a look at the forced induction section of this forum, you can see some pictures of this amr supercharger i posted up. Its belt driven and I could probably get away without an intercooler. As my superdream really is a bit too small for the 400cc diesel, I no longer have any space to mount it So it will be kept for the next project

[old clunker]

Hello Bugsy_malone 666, I'm glad that you are enjoying playing with your new diesel engine! and it certainly is a cheap introduction to diesels.
My only thoughts about it fitting it into a 250cc motorbike, is that the combination most probably "Wouldn't be able to pull the skin off a rice pudding" as the saying goes! with it's power output. Most likely best to stick it in a Honda CG125cc or equivalent cheap donor frame. Even then only expect a moped style performance, though very good fuel economy!
CVT is an option, though you could loose a bit more of your 'precious' hp output through it, by the time it gets to the final drive chain & sprocket.

As for turboing or modifying small diesel engines, when I've had them apart, they are designed perfectly, and optimised to run at a specific rpm, and produce a rated hp all day long, day after day. When you take them out of their "designed comfort operating zone" they go wrong quite rapidly. It's an unfortunate fact of life with small diesels....

Not a problem with bigger diesel engines, and ex. car diesel engines, though you can shorten their design life with greater hp outputs.

[Bugsy_malone 666]

Well that seems pretty logical.

Some of what I was looking at is old petrol engines by comparison. you look at some of the earlier villiers based motorbikes, I know some of those villiers were only about 5hp! Some of the go karts with little honda 5hp engines do 40-50mph.

So in essence, why wont the diesel be able to do the same? whats the limiting factor?

[alexanderfoti]

One word, Weight!

And drive train losses etc, most of the go karts etc are geared with a chain and thats it.

Also 5hp bikes have thin tires and relatively lightweight diesel engines. Coupled with the older gearbox design (villiers gearbox or enfield gearbox) that have quite high drivetrain losses, you would be suprised to see 40.

My 200 cc yanmar literally did 40mph tops!

[old clunker]

As stated by Alex, it's the relative weight of a diesel engine, and it has a much lower rpm range compared to petrol engines, due to the 4 stroke compression ignition design. The plus side is that is gives far superior fuel economy, and lots of low speed torque, so on my motorbike I can be quite lazy with gear changes, and just about pull away in third gear, when stationary in traffic! Try doing that with most motorbike petrol engines! With the low rpm range, diesel engines also tend to last much longer than their petrol equivalents, though it might not appear so with some "Yanclone" types! "Yanclone" are Chinese copies of the well respected but extremely pricey Japanese Yanmar L100 engine.

An approximate idea of relative engine performance, is that a 400cc 10 hp Yanclone which I have, has a performance similar to a 125cc petrol commuter motorbike, eg. max speed of about 55-60 mph. An 800cc diesel twin engine can be around 20 hp (if you're lucky!) which can give a max speed of about 75 to 80 mph.

As a guide, a 400cc to 500cc diesel engine is best suited to a 350cc to 500cc ex. petrol engined motorbike frame. It's usually a good idea to use a much stronger framed larger ex. petrol bike for the 800cc+ diesel engines, as they are very heavy. BMW's seem to be a popular choice of frame for the big bikes.

[Bugsy_malone 666]

I guess what I want is something that does about 55mph, currently I have an old sports bike thats good for 150mph! thats ok but it'll get me killed with 90bhp on tap! I havent ridden it in ages (mainly because its taken me some time to get as tyre and service it ready for an MOT) but I remember that when I use ride that while it was quick, it wasnt massively comfy to ride, not totally practical and on an average day did about 45mpg.

So then I thought I have had this kawasaki Z250 kicking about next to my workshop for what must be about 10 years now after the charging system went pop and the engine started to smoke a little, I thought great candidate for something more fun/useful.

Then came along the small 200cc diesel I bought the other day (which is a really nice little engine but I think technically ranks as a lawnmower engine as its only got splash lubrication) and I thought well its reasonable cc and diesel bhp can be a little missleading so it might be reasonable to have 125cc type power from something thats 200cc or maybe have something that equates to even 100cc power or old bike type power, which does 60mph.

Looks like I might be up against it though by your reckonings.

Thing I have found is that any bigger cc/bhp engines seem to command massive money!

[old clunker]

A 400 cc Yanclone engine will give about 150 mpg fuel economy - that's real world figures! compared to an equivalent petrol engine, so you can see that they are a lot cheaper to run.
Unfortunately welcome to the expensive world of larger diesel engines; new Yanmar L100 engines cost about £1,100 now, not including delivery costs!!
If you get lucky, you can find second hand diesel engines on eBay sometimes, which can be more reasonably priced, but you have to take your chances with how much useful life is left is still left in the engine, and how much it would cost to overhaul, if necessary.
This is what tends to hold up the development of diesel motorbike projects, the price and availability of suitable diesel engines. Engine manufacturer's don't help with the excessive prices of their new diesel engines.

If you can reinforce and 'beef up' your Kawa Z250 frame, especially around the engine mounts, it could be possible to fit a second hand 400cc Yanmar/Yanclone engine in it, if you can get one cheap off eBay - sometimes they come up for about £200. You never know your luck?!

[alexanderfoti]

I agree with you, you could spend the time and effort making this fit, but I think you will be dissapointed with the performance, or rather top speed.

I managed to get my 400 cc brand new for 385.

If you setup a search term on Yanmar L100 or l100 on ebay, im sure you could get second hand one for relatively little outlay (if you bid rather than buy it now). Mine does 55mph at redline (which the engine will happily do btw), so I think something thats 200cc will struggle.


Diesels also have high pumping losses due to the high compression that causes lower power output.

[Diesel Dave]

Diesels also have high pumping losses due to the high compression that causes lower power output.

I don't think so, pumping losses are caused by throttling the airflow like petrol engines do.

Higher compression = higher torque and more efficient burn of the fuel, diesel's also appreciate lot's of air so turbo's and intercoolers have a lot more to offer.

Direct injection diesels have inbuilt limitations as the piston weights are very heavy due to the need for the combustion chamber to be in the piston crown, indirect injection where the piston's are flat headed and the combustion chamber is built into the head are preferred for car motors and the Lombardini FOCS series motors allows them to rev up to 5000 rpm. These types also have their problems as purging the combustion chamber of spent gasses is more difficult.

If you try reving these little stationary motors beyond 4000 then you risk conrod stretch causing the piston to contact the head. This is also the reason you don't stop the motor with the decompressor as the air cushion is lost with the same result.

[Bugsy_malone 666]

yeah bigger engines get very expensive very quickly!

Basically because of the design of this 165F I figured I may be able to fit it to the bike without frame mods. It looks like I can kind of build a sub frame to hold the engine and gearbox and bolt that to the original mounts.

I know about about the high compression, 22:1 this little baby is tough to start! I think it would help if it was bolted into something!

I keep my eyes open for the yanmar type unit but have seen they arent the cheapest because they are so popular which is why I bagged this little 165F unit, 25years old but brand new for £65 maybe I can build something for round town riding(like a generator that looks like motorbike lol!).

I suspect a 500cc twin kubuta engine would be pretty good, in France they use them in little Axiam cars! but its not like they come up often or cheap and you certainly wouldnt stick it in a 250 frame!

Something else I have also seen is the hydraulic drive systems, I wondered if that would offer any advantage with a lower power engine or if a drive system with a bike more 'slack' (like a centrifugal cluch) might be advantages to limit overloading of the engine. I did think it may also be advantageous to add some small external oil pump to help lube the top end as according to the book you just kind of oil the valves once in a while!

[old clunker]

As you said, you could build a diesel powered "moped" for pottering around town on, with the 200cc diesel engine which would certainly turn heads!and would be very cheap to run.
A small commuter bike frame around 100cc to 125cc could be a suitable choice, if you can get one cheap enough. With drive systems, most probably an old separate gearbox would be the simplest, or maybe a CVT? If you can get one at a reasonable price.

[Diesel Dave]

Be very careful about hydraulic drives, really you need to be a hydraulic engineer to design a suitable system, it will need fusable links and the motors/pumps need to be capable of acting as pumps/motors on overrun or else your likely to explode something rather spectacularly.

There should be plenty of moped scooters around that may be suitable for conversion, you could sit the motor in the legshield 'gap' and use the complete drive unit in the swingarm. You will need the crank in place for the CVT variator to work but you could bolt a weight to the bug end to balance and drive it via belt or chain to the generator end of the crank choosing a suitable ratio to mimic the original high revving 2 stroke motor. Say 2:1 for starters so the 3600 max becomes 7200 at the crank which should be about right for the original 5hp stroker.

The only slight problem will be the need to cross the drive from left to right, unless you can find one of those very rare clockwise rotating motors More likely your going to need a jackshaft to sit between the two or replace the crank with a shaft that can accept drive closer to the left. Remember most of these motors are 2 strokes so the main bearings will need some sort of oiling system.

The frame may need a bit of bracing but it should be capable of supporting 2 adults, so one adult and a 60kg motor should be OK.

Cheap too as teenagers blow up engines amazingly quickly, so long as the transmission is good you have a winner.

[alexanderfoti]

I have always thought of doing this with my spare 200cc.

What I thought would be a little bit cool is something like like fox mini bike:



and have a cvt tranmission in there, issue is, Those bikes are 50 years old and hard to find, the rest of them dont have the same frame design. I suppose if I was being really adventurous I could make the frame with a tube bender, but then my thought process changes to building a bigger engined (kubota twin) diesel bike rather than a smaller one