Peugeot FE53 series 3 1994 Scoot

[fe53series3]

Apr 27, 2015 19:38:54 GMT -5 Florida Antique said:

Look at a Honda Dio and see if that looks closer to your scooter. Honda scooters are the only 2 stroke scooters that have that manifold so that's why I think except for the carb it may be a Dio engine

Just had a look at:
www.motorscooterguide.net/Manuals/Honda_SK50_Service_Manual.pdf

It all looks very similar...... and better drawings of the clutch mechanism, which I'm interested in.
If I'd had time to strip mine, I would have probably been able to tell, just from the drawings...... but they seem to have the same DNA, if not 'the same'.

My perceived problem, is that the bike needs too many revs before it launches.
Others have commented the same.

I noticed from the Dio drawings, that it has clutch shoes.
If mine has the same kit....... could they be worn, and so take longer to grab.

It seems like the bike has no walking speed.
It's not desperate, desperate, but...... it doesn't seem right........ though perhaps good for traffic light drag racing

Any ideas?

[Florida Antique]

You may need to measure your belt. Mine was worn and made it rev pretty high. While you are at it, check your rollers. If some are missing or replaced by lighter weight rollers, it will take a higher RPM to engage. There are all kinds of things that can affect that.

[fe53series3]

Apr 27, 2015 20:26:15 GMT -5 Florida Antique said:

You may need to measure your belt. Mine was worn and made it rev pretty high. While you are at it, check your rollers. If some are missing or replaced by lighter weight rollers, it will take a higher RPM to engage. There are all kinds of things that can affect that.

Thanks - this has been a fantastic help.

First - learning that the Dio and FE53 are similar engines, has opened up lots of possibilities; not least the fact that the Dio manual has much better exploded diagrams.

From your above roller comment, and the Dio diagram...... I can now see that the rollers are located in the 'movable drive face' directly located on the crankshaft.

This now explains why, when running the bike with the drive cover off...... the problem seemed to be associated with the crankshaft pulley end........ clearly it was.

The belt doesn't 'look' worn......... so I'm betting on the rollers.

It looks like I'm gonna have to make a couple of special tools though.
A front sprocket clamp...... and a clutch press.

BTW...... Is the clutch press strictly needed?

I'm hoping that the clutch nut is 28mm as per the Dio......... the FB manual states it could be a 34mm, depending on the clutch.

I have a 28mm socket...... I don't have a 34mm. 

[90GTVert]

Sometimes belts will wear and look alright if there's not excessive heat glazing them or some other form of abnormal wear, but just lots of mileage. Generally you'll find lots of belt dust in the CVT area if they're worn badly though. The best way to check is to measure belt width vs the intended spec. Usually 2mm below is a service limit, but in reality if you want original performance you'd replace belts when they're about 1mm thinner than stock.

I've never owned any sort of clutch/rear pulley/contra spring compression tool. With stock springs on small scoots I can often compress them by hand. I use my feet most of the time though. The link below starts a vid where I'm removing the clutch from the rear pulley, but you may find more of it useful if you're diving into the CVT.



You can use an adjustable wrench on the clutch if need be till you get a socket if you'd like. Some always use adjustable wrenches and prefer that, I like having the socket to fit.

[fe53series3]

First Class information..... thank you very much for that!
It has cleared up all my concerns about this drive system.

[fe53series3]

Got the flange cut out

I've made a video......... primarily because people now get less chance to experience working with steel..... so this was an opportunity to show how you can cut very tough steel, just using household tools.

[90GTVert]

Very nice flange out of an old brake pad backing! Some of our home brew pipe builders might be able to make use of that trick. Thanks for sharing it with us.

[fe53series3]

Okay..... so it's pretty much done.

Here's almost the end story, showing the finished flange...... matching the manifold spacer to the new bore, AND (Ta Dah) the bonding process.

Not mentioned was that I also 'hand surface ground both faces of the spacer', and the 'manifold spacer'.... perhaps obviating the need for a paper gasket (?)....... but we'll see all that when we see the finished article 'tomorrow'

In the meantime...... here's a taster of things to come

[fe53series3]

After around 5 hours of setting, I decided to split the assembly.
I know from past experience, that although silicone spray helps....... it's not perfect, as it can be absorbed by the adhesive.

This was a wise move.
Using a scalpel, I was able to separate the spacer from the flange/carb, and well..... you can see the results.

I've cleaned up the spacer now, and the carb/flange is fully at rest....... I won't touch it again, till at least tomorrow night.
But by Thursday, we'll have it running 

[Florida Antique]

Are you going to mate that flange directly to the intake or use the plastic spacer? A big problem with the Hondas is the threads strip out of the carburetor flange. That happened on my Aero and the PO just removed the plastic spacer and put nuts on the 2 bolts that held the carburetor on. I made a gasket and put it in there since it was leaking air into the manifold causing the bike to run lean. However, I also found that without the spacer the carburetor inlet would not properly seal into the airbox. I had to order the plastic spacer from a dealer in Germany since the previous owner threw it away and Honda has not imported parts for this bike for 20 years. I got slightly longer bolts and new o-rings and put it back together correctly. I don't know if it makes any difference but now it starts a lot easier and seems to run better however I think the only reason the spacer is there is to make it easier to remove the carburetor from the airbox. If you drop the spacer out it gives you the extra 5mm needed to pull the carb out of the air box opening. If you are going to use an aftermarket air filter, you may not need that spacer at all.

[fe53series3]

Apr 29, 2015 10:11:31 GMT -5 Florida Antique said:

Are you going to mate that flange directly to the intake or use the plastic spacer? A big problem with the Hondas is the threads strip out of the carburetor flange. That happened on my Aero and the PO just removed the plastic spacer and put nuts on the 2 bolts that held the carburetor on. I made a gasket and put it in there since it was leaking air into the manifold causing the bike to run lean. However, I also found that without the spacer the carburetor inlet would not properly seal into the airbox. I had to order the plastic spacer from a dealer in Germany since the previous owner threw it away and Honda has not imported parts for this bike for 20 years. I got slightly longer bolts and new o-rings and put it back together correctly. I don't know if it makes any difference but now it starts a lot easier and seems to run better however I think the only reason the spacer is there is to make it easier to remove the carburetor from the airbox. If you drop the spacer out it gives you the extra 5mm needed to pull the carb out of the air box opening. If you are going to use an aftermarket air filter, you may not need that spacer at all.

Interesting.
The Gurtner carb flange threads are also on their last legs, and need a nut behind the flange to secure the screws.
Thankfully I'll never have 'stripped thread problems' with my tough new steel flange

The plastic spacer is supposedly designed as a thermal barrier, to insulate the carb from the engine heat.
I'm gonna use it.
I've already re-cut the throat hole....... just enough plastic left to hold the o ring.

I have re-ground both surfaces flat.
I'm placing the o ring face to the manifold, and the flat face to the carb flange.

Because both surfaces have been ground...... I do expect the plastic spacer to act as the gasket, and I really can't see the steel warping.
If it causes problems, then I'll be forced to make a gasket.

Re the air filter....... yes this is going to be problematic.

The PHBN is wider than the Gurtner, because the outlet tube is quite long (needing normally to have to go in a rubber connector).
Also the carb inlet diameter is larger...... so it will not go straight into the airbox.

I've already removed the big stiff rubber bush....... the remaining hole needs enlarging.
I really need some hose, to fit over the carb inlet, and through into the airbox.

The airbox currently attaches with one screw to the crankcase.
I could move the connection thread backwards by adding a short bracket.

So I think the airbox can still be used with modification.

I also need a bit of tubing for the airbox inlet, that is currently pointing forwards.
I looked on the web,for what goes on to this inlet tube....... I couldn't believe it..... another enormous airbox 




Anyway..... it will be first tested without an air filter, as I don't have a pod air filter to hand....... and acquiring the hoses and making the bracket is gonna take time.

I'll allow for this when planning the initial carb setup.

BTW

The carb is currently in the oven, at about 40C...... just enough to speed up the chemical set, but without overdoing it.

Of course..... the scoot doesn't have a choke cable, as the gurtner had an auto choke.
I need to see what I've got to hand, to make one.


That's modding LOL.
You mod one thing, that causes you to then mod two other things.
 

[fe53series3]

Removed the atomiser on the PHBN 16 today....... it was chokka with the dreaded white crystals.
The only real way to clean it is to remove it, because it's a tube within a tube...... so even compressed air won't do the job with it in situ.

To remove it, you drop a bolt down the slider bore, on top of the atomiser lip, and give it a little squeeze in the vice.
Once at throat level, take an appropriate sized twist drill upside down and tap on it with a bit of wood, to fully release the atomiser.
Here's what it looked like:

 

You can see a big slap of the white deposits....... the carb bore for it was obviously just as bad.
I used a bamboo skewer, to loosen it all, and polished with a cotton bud stick.

The atomiser..... I ground a skewer to size, and used it like a pipe cleaner.
Also noted the atomiser size: GA212

Re  the mod..... flush ground the flange and outlet face, and popped it back in the oven for a final bake at around 60C.

It's looking good for a fire up tomorrow  

[fe53series3]

Installing the PHBN 16

It was the usual nightmare of bowden cables.

I needed more free cable.
In the end I settled on a primary throttle cable, and filed down the nipple to carb slider size.
With the full cable assembly dismantled, I was able to swap the old secondary cable with the new, into the throttle oil actuator.

I now had too much free cable, but I was able to insert a throttle grip adjuster...... and using a standard rubber shroud, and an actuator (large diameter) shroud on the carb side, was able to make a decent job of it.

Final adjustment was made with the threaded 90deg elbow, screwing it into the carb cap, to get just a bit of free play.

For the choke I just ran a snapped bit of bowden cable through the choke elbow....... I figured I could just pull it, to get the bike started, if need be.

Of course, the petrol hose and oil hose was now too short, so fitted new lengths

Carb Initial Setup

Without any idea of how the carb should be set up....... I plumped for a 34 idle jet, an A13 needle on N5, and a 102 main jet - and placed the air idle screw at 2 turns out.
(I'll outline the logic for this in a subsequent post.)

Having sucked fresh oil through the new hose...... with a brand new BR7HS plug, and an additional dollop of 2T oil in the tank..... it was time to fire her up.

First Fire Up

It wouldn't start!
Checked the plug...... Wet!

Wound the throttle fully open and kicked....... it fired.
Kicked again....... caught it...... and it was away. 

Let it warm.
Clearly the idle circuit was way too rich.

Tuned the idle circuit, by reducing tickover to slow..... then winding out the air idle screw.
Tickover increased...... so reduced tickover...... and wound out the air idle.
Tickover increased.

The air idle screw was now 4 1/2 turns out.
Clearly the 34 idle jet is too large...... but it was tuneable....... so we now understand the idle circuit.
The motor now fires first kick when warm (cold hasn't been tested at the new settings).

First Run

Bike launched nicely.
Assuming 10% throttle at idle, at around 25% the carb simply roars, with no more power.
On minimal throttle did a 2 Km run....... motor losing power towards the end.

Spark Plug - Lean

Conclusion

Idle circuit:- rich
Needle:- lean

2nd Carb Setup

32 idle jet
Air screw 3 turns
A13 N4

Note: The A13 @ N4 will now be already on it's taper at idle...... hence, even with a reduction in idle jet size; there will be more fuel delivered through the needle...... therefore we still expect some richness, hence the initial 3 turns on the air screw.
The air screw will be re-adjusted once warm, to establish the idle circuit position.

Looking ahead:
It is unlikely that A13 N4 will cure the leanness...... but we are looking for improvement.
Remember..... we are running without an air filter.

We are going to have to look closely at our needle options, if we are going to be able to 'keep fueling down' at idle, while raising fuel delivery at low to mid throttle.

Summary

Overall...... a huge success
Can't wait for the next set of tests.



PS. The new carb and flange looks great.
Pictures to follow when my son arrives with his fancy video phone







 

[fe53series3]

Initial Plan - Prior to first test

Because I had no idea what the setup might be, I didn't want to attempt any WOT testing, as it might be too dangerous.
I also initially didn't want the needle on its taper, at idle, so that I could better judge how the idle circuit was performing.
Hence why I went for A13 N5....... there was method to my madness

If it proved too rich, I could gor for the A28 N5...... and too lean, A13 N4.

Here's the maps:



As reported previous post...... it was much too lean.
I stuck to the plan, to see if it improved, and it did (A13 N4).

It was still way too lean...... so I decided to go for an aggressive taper: A20 N3 :



3rd Test Run
With the needle again on it's land at idle, I used 34 idle jet.
It's a touch large..... but it's tuneable...... and everything else is lean so....

Anyway, I believe I have the idle circuit under control vis a vis any needle changes; and this is comforting.

You can see what I was looking to achieve (from the map).
Launch was previously okay, so I went for greater fuel delivery from about 15% throttle.
Also, due to the extreme leanness, I figured it was time to bump up the main jet from 102 to 108.

While the main jet influence increases with throttle opening, it DOES have an effect all the way down.
An increase in main jet had to come anyway, so now was a good time to see it factored in to low to mid throttle.

The test run showed a marked improvement in performance, with throttle response to 60% opening.

Spark plug: gaining colour, but still lean. 

Conclusion

With performance tapering off at 60% throttle opening....... this may be an indication that the needle taper is correct, only that the main jet needs a further bump in size.
..... Above 60% the main jet has more influence; and this is where the motor is lacking fuel.

However.... I'm also aware that other factors may be at play.
Therefore, before moving forward to high power testing, I figured that I should really whip the top end off, for examination.

Top End Examination

It is in remarkably good condition..... almost beyond belief, in fact!

Barely any carbon on the head.
Rings moving freely.
No blow by on the piston.
Minimal glazing on the cylinder...... and even evidence of crosshatching.

The glazing that is present is all at the top of the cylinder; so it can be improved.
The ports can be worked slightly, and a touch of flow work.... but overall...... Wow!

[fe53series3]

Ah ha!....... mystery solved I believe.

I removed the top end yesterday, as light was failing, so just left a cloth over the piston.
This morning I had a look.
The piston has a No. 2 stamped into it, on the inlet side.
It therefore seems highly likely that the cylinder has been overbored to the next size.

This would explain the amazing condition of the cylinder, and head (for a 21 year old bike).

I simply wiped the carbon off the cylinder head, to bring it back to 'as new'.

Barrel Clean Up

The quality of the metal is very good..... quite hard...... harder than an AM6 barrel.

The ports are definitely not as good as the stock AM6 unit (which are perfectly shaped).
This Dio/Peugeot unit has misshapen ports, with bumps.

The good news is that these blemishes can be reached with a 3mm Dia diamond grinder on a Dremel type tool.
Where possible, sharp edges were removed, to help the rings.

The central inlet port interior has a bump that can also be easily relieved.
Other casting blemishes in the transfer ports can also be smoothed...... plus, of course, the casting bridges, that can be taken to a more pointed fine radius.

The exhaust port was fully cleaned, with one side flashing removed and smoothed.

I broke the glaze with carborundum paper @ 360 grit, then ran a honing tool through at slow speed, to get some even cross hatching scratches...... but nothing much, as the cylinder was already pretty good.

Flatted both the head and barrel faces...... both proved to be flat anyway.

Thoroughly washed all the grit off with paraffin, and that was it

I didn't even bother removing the piston...... it was clean.

4th Test Run

I upped the main jet from 108 to 112.

Attempted to start the bike without choke....... it wouldn't.
Pulled on the choke cable, and it started immediately........ a great sign that the idle circuit is cock on.

Once warm, the motor felt much crisper....... better response.
While such thoughts are very subjective....... there can be no doubt that the motor is beginning to feel so much better.

Also, further up the throttle the bike is still accelerating.
It was beginning to rain, so I brought it back and checked the plug.
At last...... colour on the plug 

I think that I can drop the main jet to 110, and take it from there.

It looks like we are beginning to get a handle on all 3 phases of the carburation

Next Test

After establishing the throttle opening at idle, I need to mark off the throttle grip, into percentages.
I'll refit the speedo, and install a tachometer.

This will enable precise feedback to be taken from each tuning change.
The bugger is, that I've just realised that there are no gears on these bikes, making testing that much harder.
Normally you can test to max revs in each gear, and take notes..... make a change, and retest; and know that the exact same circumstance apply.

I think I'm gonna have to come up with another routine.
Perhaps other members have discovered a good methodology.

Other Tasks

One thing I must do, is adjust the fork bearings..... there's too much play, and it can judder under braking.
I also really need to have a look at the rear brake.
It works fine, but......

I also need to examine the drive system, to see if I can solve the problem of delayed launch.

Either way..... good progress has been made