My Mostly Suzuki AZ50 Based build... ... Is now a Let's II

[Raizer]

Mar 1, 2016 5:49:48 GMT -5 tsimi said:

Raizer

Don't forget to get some piston pin circlips.

One step ahead of you there

Ordered Malossi, recieved Pro-X though.

So I now can't get it to make that full on metallic clunk?!?
Have tried 3 pin bearings in my 70cc kit and also in a stock 50cc set up, all sound the same on both engines!
Not sure WTF is going on there!

Measured the side to side play of both conrods at the big end, old engine 1.3mm, new engine 1.2mm, Suzuki maximum allowance is 3.0mm.


So yeah have decided to put it back together as it was and run it until I can afford a Top Racing crank and 47.4mm piston kit.

Not great videos, just realized there not even the same bores lol

My new engine with the old 50cc.


My old engine with the new 70cc.
Both videos are using the same needle bearing the Artek I've been running the whole time with the kit!

Then I cleaned up the piston, might take a tiny bit more off one of the seize spots, just don't want to go too far.


And removed the alloy from the cylinder, can't find my bore hone, have a feeling it's gone the way of my better spray gun
So hit it with 400grit and WD40, again didn't want to go too far, just took the alloy off and left it at that.


Going to go put it back together now, just had to come home to pick up one of the spare base gaskets I've got.
Really need to sort this carb out too, think I need a slow jet between the 35 and 40 I've got, and to figure out getting it a bit leaner on cold start.

[tsimi]

What am I trying to advice you here you are already on top of the game and way ahead. (thumbsup)
Very nice work on the piston and cylinder.
Are the ports inside the cylinder chamferred?
When you put the needle bearing inside the conrod does it have any forward/back play?
Is it a tight fit when putting the piston pin through the needle bearing?

[Raizer]

All your advice is much appreciated!

Lol it was you who recommended I get the extra clips in the first place when I was putting together my parts orders


The ports are not chamfered, but they will be before I refit the cylinder this evening!
I cleaned up the exhaust port before I fitted it in the first place, but didn't want to risk slipping with a file in my nice new cylinder, have realized today just how sharp the port edges are though when they shredded my sand paper!

Bearing fits nicely in the rod (which also measures within spec), snugly on the pin and the pin is a smooth almost tight fit in the piston.
There is a little bit of side play between the bearing and the piston though.
Will get out my feeler gauges and check how much.

[tsimi]

Yeah, that side play is I would say normal. Same here on my Polini Sport.

[Raizer]

Spent 45minute with a couple files chamfering the ports, then reassembled the engine and refitted it to the scoot.
Swapped to a 37ish drilled pilot jet, 106mj and still the A21 needle lifted one clip, unfortunately the decision to use Yamabond to seal the float bowl came back and bit me in the ass!
The bowl didn't come off smoothly at all and I managed to snap off the choke tube thing!

I'd been thinking of ditching the enricher, guess that made my mind up for me!
Tapped a piece of 3mm silver steel round into the snapped off fitting to seal it off.

It took a bit of cranking to get it to fire up, if I touched the throttle at all when it was trying it wouldn't start, once it did start I had to leave the throttle alone for maybe 30 seconds or more before I could start feathering it another 30 seconds or so and it was sweet as.

Noise seems to be all but gone too!!

Revs were hanging when I let go of the throttle and it sounded lean mid throttle, so I swapped the A21 to the A33 needle in the middle clip


Super rich!!
Fairly sure that is variator rattle in the vid.
Smoked the shed out and called it a day, not sure where to go needle wise yet.

[Raizer]

The more I look at the Dellorto needle chart, the more I think the A20 needle is the one to try next


A13 & A21 were both a bit lean mid throttle (seized with the A13), A33 is clearly way too rich, so yeah A20 looks like it should be the winner to me.

[Jwhood]

Do you have starter gear on in the back of variator? If so after a while they get wore out and that's what you here rattling, also could be wore variator guides and back plate is jiggling around

[Raizer]

Putting the CVT cover back on has dampened a lot of the bit of noise that was left.

I'm starting to get lost with tuning this thing, started this morning by swapping to the A20 needle, clip centred, 106mj and the about 37sj.
Seemed ok but maybe still a touch lean, lifted the needle one, was a bit better.
Bit of 4 stroking around 1/4 throttle and I was thinking a touch lean at around 3/4, was having trouble getting it to idle and had to have the air screw most of the way in.

So I went to the 40sj, 108mj and left the A20 lifter one clip.
After bring the air jet out to somewhere just over 2 turns it idles nicely and throttle response is pretty good!
Test ride found it lean and the revs hanging in the mid to 3/4 throttle range, WOT seems pretty good (am ordering some mains bigger than 108 though)

Lifted the A20 to it's richest spot, I think it is still a bit lean and the revs seem to hang a bit?


So now WTF do I do? A07/A08 or something? But then the A33 which also tapers down to 1mm seemed miles rich yesterday and that was with a smaller MJ??

Have started making some brackets to hold the airbox secure, refitted the CVT cover and kickstarter and discovered that my batter wiring is an absolute mess of half broken loosely crimped terminals and solder severely melted insulation on under size wiring, so am going to rewire that!! Will add a jump start/charger plug too.

[spaz12]

Depending on the setup, most of the time the clutch is still engaged so I don't know how you would know that you that the revs are hanging at mid to 3/4 range? The scoot sounds pretty good in that last video.

How do your plug chops look now?

[drc174]

you are overthinking.

go for a good ride, check the spark and go from there

needle and idle are cosmetics, MJ is where its at for the power

get that right first, then do response and half gas

[Raizer]

Ah I wasn't taking the clutch into account! Ever since the seize I've been super paranoid!!

Only done one chop so far today and that wasn't with a new plug just the old one freshly cleaned, but it was a dark caramel from a WOT chop.
Ran out of time to do any more chops today though, have got 2 new plugs sitting here for tomorrow.


It feels pretty good to ride too, decent torque right from the point the clutch engages and a strong pull in the mid range, af anything it almost feels slightly weak at WOT, will do a WOT chop tomorrow.
If I open the throttle any quicker than I did in the video it lifts the front wheel/on gravel it spins the wheel and tries to take off sideways haha

Have learned 2 things about starting it too, 1 is with electric start it needs to be turning over FAST to cold start, 2 is that the kick starter seems to start it a lot easier than the electric start hot or cold!
Think my dodgy battery wiring and ancient alarm back up battery don't help at all

[Raizer]

Mar 2, 2016 23:44:37 GMT -5 drc174 said:

you are overthinking.

go for a good ride, check the spark and go from there

needle and idle are cosmetics, MJ is where its at for the power

get that right first, then do response and half gas

That was my exact thinking when trying to tune the 50cc/stock carb, but after seizing this engine just running it in, I'm being a little cautious with the mid throttle/cruise as it will see low throttle more than WOT in daily use.
the speed limit here is 50k, I'm sitting on just under 7000rpm at barely more than 1/4 throttle at 50k.
I'm not saying I'm going to be sticking bang on the speed limit all the time, but I don't want to kill the cylinder just cruising with the wife on her scooter.

[drc174]

oil pumps that run dry need a good 10-15 to fill up to the carb again. let that happen first

[Raizer]

Didn't do too much to it today, rode it for about an hour without seizing it so that's a win to me!
Leaned out the air screw about 3/4 turn, just until it gave it's highest idle, seems to have improved acceleration from idle up to around 1/2 throttle if not higher.

Changed the plug and checked it after just cruising around a while no WOT, nice caramel colour, will do a WOT run tomorrow, wouldn't be surprised to find it a bit off as to me it feels like it's lacking a bit of power in the top end.

Clutch isn't disengaging before just under 4000rpm, annoyingly it's now engaging at a bit under 4000 too, used to be closer to 5500 so I don't know wtf is going on with it!
I can see one of these coming with my next RP order somehow...

www.racing-planet.de/clutch-adjustable-evolution-racing-110mm-for-cpi-keeway-morini-derbi-minarelli-100-p-247268-1.html?backcPathco=5&cPath=4855_20549#.VtlGLNCIXhU
Well that's if my new business takes off and I actually have any scooter money in the near future lol

Fitted up the airbox bracket I made an painted yesterday

Super solid!
Need to have another attempt at making a front one too

That's how much further out and back this carb pushes the airbox.

Managed to get the elbow to seal both at the carb and the box, used a bit of teflon tape at the box.


Started rewiring the battery, can't believe just how bad it was!!

Then I added probably the most important mod yet


Went a bit far with the dremal and messed up the hole



Flicked on the key and

Success! No more flat battery from GPS + Music while riding!

Started wiring the LED too

AC in, DC out, weather pack fittings FTW.

And finally for today I've started cleaning up the faded greyed plastics a bit tonight

Not perfect, but much much better than they were!

[Raizer]

Cleaned up the rest of the plastics and got it looking like a complete scooter again!



Am thinking of tearing it down in the somewhat distant future and giving it a quick paint job, need to find a new tail light and maybe some better condition plastics first -not to mention money and enthusiasm to spend hours sanding!

Finished wiring up the LED lightbar, hooked it up on a switch so it can only be turned on when the high beam is on.
While it looks a little odd on the front, I think the trade off is going to be worth it

It's damn bright!!

My centre stand needs to have the mount plates remade, the guy who welded up my Stage 6 pipe is going to watercut some new plates out of 6mm plate and weld them on for me, we're going to lift the stand maybe 10mm at the same time so the bigger tyre doesn't touch the ground when it's up on the stand.

Next mission is to tidy up this mess

Have got a couple ideas for it, need to work in mounts for the CHT display and the volt meter too.