Time For A New Gear Swap Thread?

[Wheelman-111]

Greetings:

Simplify.

Tranny has 3 shafts. Let's name them:
1. Drive - has clutch on outside end, small gear inside case.
2. Countershaft - 2 gears, bigger one -2a- is pressed on and mates with Drive. Smaller gear -2b- is machined into shaft, mates with Axle.
Whole thing spins backwards.
3. Axle - bigger gear on one end, wheel on the other.

1 : 2a = Primary reduction. (Stock on '87 Aero is 12/34 = 2.83)
2b : 3 = Secondary reduction. (Stock on '87 Aero is 12/47 = 3.9167)

Multiply these numbers to yield 11.097 overall stock gearing. (Forget the variator for now...)

There are three ways to change these ratios:

1. Swap drive shaft/small gear AND the larger countershaft gear, which is pressed on with or without (??) splines.

2. Swap the countershaft with its small gear, re-use the larger countershaft gear, swap the Axle gear.

3. Swap all 4.

What you cannot do is just swap both countershaft gears because then one or both would no longer engage the Drive or the Axle gears.

Malossi sells it both ways:

1.




2.




In fact these are pictures of two sides of the same carton! Those wacky Italians!

The Malossi kit I received came with a new #1 shaft.




A 16-tooth primary is machined as part of the shaft. It replaces the stock Clutch drive shaft, which has only 12 teeth. AFAICT it does not come off. The 32-tooth separate gear replaces the 34-tooth stock countershaft gear, 2A. The 12/47 secondary ratio is supposed to be retained, obviously. This gives a new ratio:

16/32 = 2:1
12/47 = 3.9~
Multiplying = 7.833~
I previously calculated - incorrectly - a 5.67 ratio, but that was because I didn't know which gears were to be replaced. 8-ish :1 might almost work.

Here's where it gets fuzzy for me: On the '87 Aero, the Axle gear has splines. Reading ChevyGuyJay's long thread, evidently so does the the larger (2a) gear. Is this correct?

The Malossi kit gear above is not splined, so countershaft splines have to be machined down, also correct?

What about the Axle gear on post-94 bikes. Does it have splines? The kit gear in the first photo appears not to have them.

It may be worth one more disassembly for me to pull 2a and check to see if there are splines firsthand, unless someone can tell me offhand..

Thanks!

[evilone]

Larger gear is splined on the 87. 94+ no splines, pressed on.

[chevyguyjay]

evilone is right. but i broke the rules a bit lol. heres the pic of my gears that i had to machine. as for the axle shaft, i got a stock dio shaft for the other gear. i know....very blurry pics. sorry.

[Wheelman-111]

Greetings:

CGJ, your pictures are excellent. Just look at some of mine for an example of Bad.

[Wheelman-111]

Greetings:

Here's what I know so far. My particular version of Malossi part 67-6458 shown in the first post IS intended to fit SE50.

In ChevyGuyJay's thread, the largest Axle gear and the small Countershaft (2B) gear are replaced with a different pair. (He had to obtain an SA50/Dio Axle to install the bigger gear.)

In my setup it's the other pair of gears that are replaced. The kit came with a new Clutch Driveshaft, with 16 teeth on its gear instead of the stock 12. Honda-san recommends installation method in Service Manual using an accursed special collar and bolt. The kit also furnishes a 32-tooth Countershaft (2A) gear, replacing the stock 34-toother.

Speaking of teeth, these kits evidently are becoming as rare as those of the proverbial Chicken.

I've been able to find "spare" used parts online. Rather than take a risk with Flash's own parts, I will install the new Clutch - Drive shaft on a used transmission cover. I also found a used countershaft on which to fit the new 32-tooth Malossi. That will make the whole operation truly Swap-Out and Bolt-On.

The local Honda dealer (Cowboy Honda) Service manager thinks he has the special tools lying around, or can work around with the shop press & spacers/collars. I may buy new seals and/or bearings from them if needed. Installation of all should be free if I do.

[mousewheels]

Wheelman-111 asked for gear info from other Honda scooters in another thread. This thread is better to post the info.



Note: Diagram for simplicity shows a 1 piece assembly for 'B' & 'C' gear.
For 94 up its a 2 piece, info those in this thread already know.

[Wheelman-111]

Greetings:

All Hail Mousewheels as the Master of Scooter Cyber-Gearology. (BTW, How come your avatar is a cat?)

It's interesting to note that the Sprees are pulling that 6.3~7:1 ratio. Now it's no wonder why their acceleration is liesurely! I wonder what the Spree belt reduction factor is? I'll bet it's over 2:1.

[mousewheels]

Spree pulley ratio is 1:8:1, Overall ratio - engine to rear wheel is 12.45:1

A stock '85 Aero variator is 0.8:1 at high speed giving 8.87:1 engine to rear wheel.

I think Kenny's the one that says the Spree is like a cycle stuck in 2nd gear.

--
Re: Avatar - my cat is really a fox, as in 'honda roadfox'

[Wheelman-111]

Greetings:

So what happened to the Mouse? I'm confused!

[mousewheels]

So what happened to the Mouse? I'm confused!

'mousewheels' name is after a barn find. '87 Aero, When I picked it up, it was just like the pic, fairly complete & dusty, but it reeked of mice. Getting it home, I found mice had nested in the front covers, airbox (cover missing) and the rear panels. Was pretty amused that in an entire barn, that Aero was so attractive to mice.

Someone on this board had a big mouse problem too, ate up his wiring.
http://www.hondaspree.net/phpBB2/viewto ... light=mice

[Wheelman-111]

Greetings:

Used AF05 tranny cover? Check. New 6202 and 6203 bearings and oil seal? Check. Malossi 67-6458 kit? Check. HF 3-pound blind bearing yanker? Check. Bearings yanked out? Check. Special tool from Honda-san to pull the drive shaft onto that 6203? Uhhh, no but friendly dealer says he can do that along with the press job on the countershaft for 1/2 hour's labor charge. $55. Still cheaper than buying the tool and finding a press. Done and done.

I now have a bolt-on swap kit for 7.83~ gearing. Pics below:




THis used cover looked pretty disgusting when I got it. How did I clean? First I pulled the bearings with my handy-dandy new blind bearing puller set:





Then I handed the cover to Honda-san's friendly dealer. They stuck it in their parts washer. You could eat off it when it returned. Mac and cheese, in my case... Another view of the installed Malossi gear set:




The pitting in the cover was corrosion, not dirt. Honda-san can't work miracles...




Swapping back and forth from this point will be truly bolt-on. NO parts to buy. If I ever move to the hill country, I'm ready...

[Wheelman-111]

Greetings:

Malossi gears installed! Too many changes at one time can leave one perplexed; the bike is SLOWER! Topped at 42 tonight. Was 47 before seize.

Installed K&N filter, 89 jet, same 0.5mm carbon reeds, and gears tonight. Takeoff is a little slower, and top end seems to be limited by premature variator upshift. Can't get the revs up as high as before. Feels like I need lighter weights or stronger contra spring to get back into powerband..

Not sure about jetting yet. Temp staying well below 300, so I don't think it's lean, but hard to tell. That K&N sure is loud!

Advice welcome from here.

[noiseguy]

I'd get it running on the previous (stock?) airfilter first with the new gears before adding the K&N. I'm losing track; did it have the stock airfilter before the gears?

Other opinions?

[Wheelman-111]

Greetings:

Thanks, NoisyDude
Yes the stock airbox was on until I tested the whole shootin' match of changes last night; Different jet, different air filter, 8:1 gears. Too much at once and I should know better.

I had one heartbreaking hiccup, quickly resolved. It seems my BPR8 Plug is a dog. When I first fired up it seemed fine on the bystarter. Within ONE minute it was bogging, coughing, wouldn't take throttle, finally stalled altogether. Reinstalled the old BPR6 and it ran sweet except as noted. The 8 plug was on it when it seized the other night. It was binned quickly and without ceremony, in case I'd ever be tempted to put it back on...

I'll try putting the stock filter box on first, see how it goes. Less work.
Why don't we move this over to Aerophile Jetting & Tuning?