New to forum, mods for a dio

[Wheelman-111]

Greetings:

Scoring a Dio in any condition from a rubbish heap is an incredible stroke of luck for which many if not all Forum members may loathe you. Potential aplenty, even from the stock bore. Unless you plan to move to the BBK soon, I would retract my advice favoring the 8.4s. You can compensate a little with lighter rollers in the short term, but I believe 0-10KPH will be a bit painful without the added oomph of 72cc or more. 9s are for sure better for a 50.

Honda sold the 1100XX here Stateside too, and for a year or so it was the fastest production motorcycle made. Honda gave up the Top Speed Chase when the Hayabusa/ZX12 rivalry began, and dropped the 'Bird altogether from its US lineup. Evidently a "Gentleman's Agreement" to keep speeds below 300 KPH was violated by the first-year 'Busa, which came out of the crate capable of 192 MPH by one magazine's test. I'm sure Honda-san had his reasons, but I for one was disappointed that a "Stock LSR" bike was no longer available from Honda. Why are you gearing it down?

Pick your Dio gears carefully, they're a bit of a PITA to swap out. Also verify (and maybe post for us poor US slobs who've never even seen the AF18's innards?) the shafts' diameters are the same as the AF16 gears whose aftermarket is so plentiful. I was happy with the 9s but concerned that a long downhill might spell doom for my bore. The 8.4s are a bit pokier right off the line, but the difference disappears once the clutch is fully engaged, especially with the lighter rollers.

[hughjass63]

Thanks wheelman.

I hope people don't hate me for finding the dio. I thought they might think I'm a bit of a loser for riding a scoot from such humble beginnings. It should be noted that my dio isn't even close to the condition of yours. You will see when I eventually get a photo out. The reason I haven't is that I am under pressure with my blackbird to get it registered in the time frame allowed after repair, and I have just finished respraying it yesterday. It has sucked a lot of time and money for many months. If you want you can see my blackbird story at http://www.cbrxx.com/introductions/8962 ... peful.html. I think you have to join to see the photos, but the text should be okay.

I love the blackbird for all that it is. But what I am finding with the Dio is a return to my roots. My father used to have a mower repair business, so I grew up immersed in simple air cooled single two and four stroke engines. The Dio reminds me a lot of them. It has an engine that you can understand, pull apart, fiddle and enjoy. We also had a fair few, what were then known as, 'step-throughs' to learn to ride on, so I am quite familiar with the turf. The blackbird is not so straightforward. (Although I am finding the Dio clutch and gear mechanism intriguing and quite a steep learning curve.)

Regarding the gearing, I still think I will go with your original advice, but get the BBK and gearing in one go. I have sought a quote from yan and hopefully I will hear from him soon.

Thanks again for your patience and advice. I realise the Dio is not what you have in the states, but i seemed to be finding all the right info on your forum, so I joined. No other forum seemed to cover things so well. You guys have been very helpful. - jon

[tazland001]

I had a fourstroke honda come in from japan once. It was looled almost like a spree. I think it was called the Honda Pax. Sluggish. It was a 1987 model. I ended up puting a pal engine on that scoot.

I have a fall special. 50mm kit RIK and gear ratio(2 sizes to choose from) for only 125 w/free shipping.

I have a dio engine in my elite. Its actually the first Dio motor with the skinny crankshaft.

Marc

[hughjass63]

Honda sold the 1100XX here Stateside too, and for a year or so it was the fastest production motorcycle made. Honda gave up the Top Speed Chase when the Hayabusa/ZX12 rivalry began, and dropped the 'Bird altogether from its US lineup. Evidently a "Gentleman's Agreement" to keep speeds below 300 KPH was violated by the first-year 'Busa, which came out of the crate capable of 192 MPH by one magazine's test. I'm sure Honda-san had his reasons, but I for one was disappointed that a "Stock LSR" bike was no longer available from Honda. Why are you gearing it down?

Sorry, missed this bit. I am gearing down blackbird just one tooth on front sprocket because it will be used a lot for commuting. Traffic is fairly dense in Adelaide and the clutch can get a bit of a hammering with standard touring gearing. It will also wheelstand more easily with the lower gearing (not, of course, that I would deliberately want to do so).

[hughjass63]

Finally got some photos. Here it is cleaned although I have already let it get a bit dusty. But no seat as it is being reupholstered. Waiting on BB kit and variator.

[burnt_toast]

looks very nice for someone to throw away, you scored big ausi man

retro 80's color scheme FTW

[hughjass63]

Well, time to continue the story.

Fitted 50mm big bore kit (thanks Marc), changed to a 'race' variator (don't quite know what makes it race), and installed new kevlar reinforced belt. Ened up using rattle gun on variator.

The original piston was rooted (in Australia this means 'screwed') from previous owner having run the scoot with no air filter element.

Some problems on the way: Had the scooter up on a bench, tried to pull it into better light, and the whole scooter fell off and smashed the rear tail light, scratched the paint by the front blinker, and spewed 2 stroke oil all over my workshop. I felt somewhat 'uncomfortable' about the incident and only stopped swearing about 20 minutes later. Very ugly.

Still have the dio on the bench, plenty of 2 stroke in the petrol (gas), so is billowing plumes of beautiful blue smoke.

[mookie]

[quote="hughjass63"

Then when I saw how affordable and plentiful were dio bits, and how enjoyable it was to ride... I was hooked. [/quote]

by jove !- i thinks e'z got-tit!!!

[Wheelman-111]

Greetings:

Great job on the cleanup, mate! (Thet-thar's per-nounced "Might" for us Yanks...) Except the part where you dropped the thing; an honest wrench, thanks for sharing a laugh. You are not alone in the Bonehead Mechanic Club. Or the Cuss-Prone Club

I think you'll find the "Race" variator's diameter to be just a hair larger. The roller ramps are also more "Aggressive", whatever that means. In practice however the improvement is tangible in terms of take-off and top speed. You can re-sell those flat-spotted rollers at great profit. Dr. Pulley does...

[hughjass63]

A couple more pics.

[hughjass63]

Okay. The story continues... with some problems.

I have installed the 80cc big bore kit, new race variator, rollers, and belt. Also drilled four 1" holes in the stock air filter, and installed 1mm jet (redrilled old one). Have a small amount of two stroke oil in petrol to keep things slippery (and a bit smokey).

But I am having the same problem as before the rebuild with acceleration, in that it seems to take about 5 seconds to pick up enough revs to take off. This problem is particularly noticable after sustained throttle. Once the scoot is moving the power is fine, but seems to be quite lacking in response when slowing down and accelerating again.

Any ideas?

[aerorob]

im just shooting from the hip and throwing things out there, but it sounds like a clutch issue to me. like in a car, if you have a shot clutch, getting moving from a dead stop is difficult, but once the clutch finally engages and you get moving your game on. in the case of the scooters, your rpm dictates if the clutch is engaged or not, maybe you have a weak clutch? that might explain why once you are moving your acceleration seems normal, because when your scooter is in motion coasting and you give it throttle, its easier for your scooter to engage the clutch because you already have momentum taking a load off of it.
even if im wrong i hope it then eliminates a possibillity..ha

[Wheelman-111]

Greetings:

The clutch idea is a good one.

Another possibility is that your engine's access to mixture is limited despite your drilled airbox. Stock pipe and carb?
1mm (~#100 main jet sounds small for a 50mm bore, but not if the intake is restricted by a high-resistance filter.

How does the plug look? If it's Chocolate or darker, try doffing the filter and see if it grabs revs faster. If so, consider a pod filter but you may need to jet up for it.

If the plug is white, look for air leaks: carb insulator, reed block, head, base and exhaust gaskets. Jet up to 110-115 unless you find leaks.

If the problem persists, consider testing with the airbox holes taped over.

As a last resort, inspect reeds for floppy fatigue. Glass stock Elite reeds seem to tire with miles and duration of fuel exposure. Metal ones sag just before they break!

BTW
Your plastic shroud should snap together with a satisfying click. Gaps can be a Very Bad Thing. Some cylinders reportedly require substantial fin shaving to let the shroud fit tightly. At the very least, tape the crack and make sure there are no places where the cooling air can escape before doing its important job.

Good luck!

[hughjass63]

thanks for the advice guys.

I don't think it is the clutch, as the 'bogging down' is still an issue when the clutch is fully out, ie if going 40kmh at full throttle, then back off for a few seconds, then accelerate again and it will bog down. That said, I haven't opened the clutch yet, so cannot really comment objectively on its condition.

I am starting to suspect it might be something with the reeds. I have notices that sometimes the engine seems to flood easily, and that it can get quite oily around the exhaust outlet, almost like fuel is pouring too easily into the combustion chamber. Also, the feeling of the bogging down with throttle is like it is trying to clear fuel.

Have pulled out the reed block and the reeds are all there and are the clear type. I am guessing they are the standard ones. How do you know if they are stuffed? Thinking that the scoot has some 27000 km on it, could it be that i should just put new ones on anyway? If so, which ones?

Have not checked the plug colour as yet. (I want to get a new one before I do further experiments)

Thanks again for advice.

Jon

[hughjass63]

PS - Wheelman, I can't seem to get the shroud to snap together. It wouldn't on standard bore either. Might have to rig up something else.
Jon