Fickle Females

[Lunytune]

Since the Elite E was our first 49er, wife has a special affection for it. After all, it is smaller, and really easier to ride for a short person. BUT, since she's been letting our daughter ride it when we do rallies, and she has been riding the SA/SR scooters, she notices the difference in power, especially on takeoff, 0-10mph. I've got Tazland's kit on the shelf, waiting for the topend to die. She wants more power NOW. So guess what one of my winter projects will be? It's going to require some porting (Assuming Tazland went with NQ50 porting), and anything else I can come up with. Dome piston should help.

What's the deal with the clutch? Stronger springs help? Availability? New belt is definitely in order.

[SpyderMike]

not sure if the clutch springs will help more, but a thicker belt might (see 1/2" belt mod)

[Clivester]

Since the Elite E was our first 49er, wife has a special affection for it.

Does it have anything to do with how easy it is to pop the Elite E onto the center stand? Maybe adding a side stand to the SA50 would do the trick.

[Lunytune]

Since the Elite E was our first 49er, wife has a special affection for it.

Does it have anything to do with how easy it is to pop the Elite E onto the center stand? Maybe adding a side stand to the SA50 would do the trick.

Here's something my wife sent to me last night. (We have separate computers networked)

"Women and cats will do as they please, and men and dogs should relax and get used to the idea." -Robert A. Heinlein

One thing Heinlein didn't say is that not only must we get used to the idea, we must also accomodate our women.

The center stand may be part of it, but truth is, the Elite is 50lb lighter, 3 inches shorter (she has short legs), seat is more comfortable (SA/SR seat curves up, pushing your butt forward uncomfortably). And for some reason, she likes the brakes better. I've tried to adjust the SA/SR brakes, but can't match the feel of the "E".

[808BMW]

Is there something wrong with the top end that makes you think it's going soon? I'd put on the tazland kit, and practice honing+ porting on your stock setup.

[Lunytune]

Is there something wrong with the top end that makes you think it's going soon? I'd put on the tazland kit, and practice honing+ porting on your stock setup.

No, stock top end is healthy. Starts easy, runs good, just needs more power on takeoff. To make it more noticeable, we live on a hill and our back driveway is on a slope. (we live on a corner, scooters are stored and parked in the back.)

I've been following the recent threads on porting and also reading up on the threads in the "Advanced Tech Docs". There's lots of good stuff in there. It's just a path I haven't been down yet. I am advernturesome though, just need a nudge. Shucks, I learned reloading ammo without a mentor. Now that's really scary. I did have books to help. Not many books on porting. This forum is my mentor.

[808BMW]

A stiffer center spring will give you take-off at the expense of cruising speed (most noticable at low throttle cruising)
My road is an 18% grade and I do fine with a 1000 center spring (although I do have a ZX trans).

Porting is a black art. My biggest recommendation would be to use something you don't mind completely ruining (an old stock bore), and go slow. You can always take it apart and re-grind that "little bit more". If you go crazy at first, you'll probably put your bike together and it won't run, and there is no going back.

[Lunytune]

You can always take it apart and re-grind that "little bit more". If you go crazy at first, you'll probably put your bike together and it won't run, and there is no going back.

Yeah, this is not like running back to the lumberyard to buy another board for the one you cut wrong. And I usually find another use for scrap boards. Not much use for a cylinder that's screwed up.

So now you got me puzzled on the porting. I'll probably back off that. The dome piston and small amount of displacement increase should make up for a lot. I will probably go ahead and polish the ports though. That can't hurt anything.

[capturedbyrobots]

As a general rule, you can raise the exhaust port a very small amount,
and widen the exhaust quite a bit to get more revs and more power out of the motor.
I've done this before with great results. Just do a little at a time.
Also be sure to chamfer the ports you adjust (smoothing the edges),
I use the dremel and 220 sandpaper for the chamfering.

I would not personally mess with the transfers at first except polishing.
Often I just port the exhaust first and get it and the transfers polished.

If you just widen the exhaust at first and do a little at a time,
and be sure everything is very smooth and very clean, you can't go wrong.

As well, check the squish. You can often lower the squish on these motors
to about .5mm (either mill the head, or switch both gaskets, base and dome to copper .005 gaskets...
I use sealer alone on most of my motors once I have the squish set right.
You will need to use premium gas if you're running higher compression though.
The added compression gives you a great kick in the seat
and often it will let you rev higher too.

[Lunytune]

As a general rule, you can raise the exhaust port a very small amount, and widen the exhaust quite a bit to get more revs and more power out of the motor.

Hadn't thought about widening the port. Tell me more.

[Bear45-70]

As a general rule, you can raise the exhaust port a very small amount, and widen the exhaust quite a bit to get more revs and more power out of the motor.

Hadn't thought about widening the port. Tell me more.

Making the port wider is the equivalent of using more lift with a 4 stroke cam. While raising the port is the same as increasing the duration of the cam. A wider port retains the low end torque of the stock set up while still allowing the engine to breath better at the top end for more power. I am going the wider route, since the Spree's fixed ratio drive doesn't help the acceleration, I don't want to hurt the low end power at all.

[Lunytune]

Making the port wider is the equivalent of using more lift with a 4 stroke cam. While raising the port is the same as increasing the duration of the cam. A wider port retains the low end torque of the stock set up while still allowing the engine to breath better at the top end for more power. I am going the wider route, since the Spree's fixed ratio drive doesn't help the acceleration, I don't want to hurt the low end power at all.

Thanks Bear. Putting it in 4 stroke vocabulary helps a lot. You know how my mind works.

Now quit scrapping with the bratty kids and let's get down to the serious business of getting our scoots to run better. My Fickle Female thinks I can solve all problems, and I don't want to let her down.

At this point, we're talking exhaust. How about the intake? Will widening the ports help there too? How much should each be widened? Or is it critical?

[Bear45-70]

Making the port wider is the equivalent of using more lift with a 4 stroke cam. While raising the port is the same as increasing the duration of the cam. A wider port retains the low end torque of the stock set up while still allowing the engine to breath better at the top end for more power. I am going the wider route, since the Spree's fixed ratio drive doesn't help the acceleration, I don't want to hurt the low end power at all.

Thanks Bear. Putting it in 4 stroke vocabulary helps a lot. You know how my mind works.

Now quit scrapping with the bratty kids and let's get down to the serious business of getting our scoots to run better. My Fickle Female thinks I can solve all problems, and I don't want to let her down.

At this point, we're talking exhaust. How about the intake? Will widening the ports help there too? How much should each be widened? Or is it critical?

Looking at the intake porting (I happen to have an SB50 jug in my hand) I don't think there is much to be gained there. The manufacture has provided at least twice as much intake port area as exhaust. The intake charge is also very cool compared to the exhaust (hence it is denser), which also helps for the intake flow, it is also under pressure from the crankcase (a form of supercharging). I would suspect that unless you went with a much bigger carb, intake manifold and reeds, that the intake porting would still be adequate in most cases. If you could find a very good exhaust system that was tuned to your setup almost perfectly then that might change things.

Looking at the exhaust I think a lot can be gained by porting out the exhaust passage from the cylinder port to the exhaust flange. It looks very rough and small. Bigger and smooth port walls can only help. Just be careful of grinding the port walls to thin.

If you do decide to do some intake port grinding I would think that down at the crankcase to jug connection would be more worthwhile than the ports themselves. If you are gonna grind intake ports, do a very little on the sides of each port as you don't want to change the mixture flow thru and around the chamber to much, it can screw up the exhaust purging.

[Lunytune]

Looking at the intake porting (I happen to have an SB50 jug in my hand) I don't think there is much to be gained there. The manufacture has provided at least twice as much intake port area as exhaust.

Is that a Tazland jug or OEM jug? I've got my Tazland jug/piston sitting here on my desk in front of me, and must agree that there is ample intake porting. Something else I see is that the back port (I believe that is referred to as the boost port?) is straddled by the ring gap pins. I wouldn't want to get anywhere near the ring gaps.

I don't really see a lot of room for enlarging the exhaust port without weakening the walls of the flange. However, Tazland's walls do look thicker than OEM AF16E jug. I've got it in front of me too.

[808BMW]

Watch out when widening your ports, more port width = less ring life.
As your piston passes the widest opening of the exhaust port, the ring can enlarge slightly (less of a complete cylinder holding it tight).