The Abominable Honda Elite

[kosmos]

I'm going to make a build thread here about my 2001 Honda Elite SR to document what I do and to maybe get any tips and so others can see what I do and what happens along the way.  

I have a stock 50cc Honda Elite with the af16 motor.  I just added a Malossi 47mm cast iron BBK to it.  Besides stock it has a few mods but on the stock side.  I have the japanese dio keikin stock carb, intake manifold and airbox.  Ive taken the snorkel out of the airbox for better airflow.  Ive had this scooter before with a corsa bbk and a pg long pipe but, I had an airleak I couldn't hunt down on it for a long time.  My PG Long got the baffle rattle and I seized the piston in the cylinder putting the piston on backwards.  Cylinders still good just needs honed and  a new piston.  But not going that big right now.  My airleak came from the oil pump delete plug.  At least I assume it was until I retest it but really don't want to do all that right now.  Never got it to get rid of the cut out until I put the stock pump back on.  The plug uses a different place for the gasket compared to the stock oil pump and every time I put the plug in, it would come back out with the O-ring split in half.  Yes I used oil, trans fluid, deep creep, even caliper syn-glide grease that won't swell rubber and works with brake caliper sleeves, and the o-ring always split.  I put everything back stock until I only had the plug pump left so remembered that problem, and even tho I had pressure tested it successfully, it still cut out when I'd rev the throttle back about at 1/4 throttle.  Anyway, once I put the stock pump back on and worked through a couple of other issues like the carb float, it tuned and doesn't cut out anymore. 

Wasn't back totally to stock.  Didn't have the stock exhaust anymore, or the stock carburetor, except for the dio stock version.  So I bought a stock-ish JWS exhaust.  Honed a good low mileage stock bore and got a new piston and ring, negated every issue it could be except the plug pump, and still wouldn't stop cutting out.  other than that, my cvt had an aftermarket variator, now has a Keli, and polini adjustable clutch pads and a clutch bell.

Got it running and decided to change the CVT to the ZX transmission, basically the GY6 qmb139 setup.  Using a 669-18-30 belt.  got it running good, ran it today for about an hour, top speed around 44mph.  92 main jet and a 38 pilot jet in the carburetor.  no overheating, revved back on the throttle good.  takeoff is good.  Decided that I'd put my Malossi 47mm cast iron kit on that I'd had in a box sitting around for like 4 years. 


Had been chamfering the ports and oiling it up recently to get it ready.  Went out tonight and slapped it on.  I live on a 55mph road so its hard to go up and down the road out to anywhere and its a good 3 miles to the nearest side road to get me off this road so, wanted a little bit more top speed.  Just started it up tonight for a heat cycle.  Small exhaust leak that was pretty audible when it started.  Looked and seen oil spitting out around the exhaust port on the gasket.  So I took and changed it to the ring gasket the kit came with.  Put the exhaust on the cylinder first and got it all the way up on there and tightened those bolts down before I finished by tightening the exhaust frame bolts. 

I'm using a 102 main jet and a 42 pilot jet.  Got the suggestion from another build with a 47mm Malossi stock everything else basically setup I'd read.  Pretty sure the pilot jet is right.  The main jet I'm not for sure, think it might be lean.  This is the biggest main jet i have so, I have 2 options.  Change to a larger carb I have or, buy more main jets.  Then I gotta play the waiting game.  Or go through the whole process of changing out the carb and starting from scratch.  I have a 17.5mm arreche I think fits on the stock manifold and I think I had dremelled it out for it to work with it before or, swap out manifolds and go to a 21mm dellorto phbg.  Wonder about mpg, wonder about the top speed I'd get from either or this one.  

Here's a couple of videos of the first startup and 2nd startup with an interuption when I hit the stop video button.

first start
2nd start - 1st half
2nd start - 2nd half

[kosmos]

First ride video. This is down the road a couple of miles from the house. I had it shut off on me and bog out. Anyone have any idea why this would happen? It seems to me like its loading up on gas and flooding out rich but, the temps where high, I got 370 going down the road about 2 miles and climbing. So that seems like my main jet is lean.
First Ride
Heres a couple of cuts from the ride to shorten it. The first is when I first started it up before I left and some revving with the throttle and the way it sounds. 2nd is the beginning of the full video with the long straight stretch with the bogging down and died on me

streamable.com/lg9ulb
streamable.com/pxfe2j

Any ideas why this would happen? Maybe the needle is rich or lean? Ive went up from the 95 main jet to a 98, still got hot. went to 102 and won't even get going. Going to try a 100 but, its odd, seems to be dying from flooding out and happens after I run full throttle for a while. But temps are hot at full throttle.

[hippo008]

I think you need to go backward and do some engine checks before you start tuning. No amount of tuning will overcome a poorly setup engine.

First step here is to pressure test. I like to run all pressure tests twice. Pressurize crankcase for 10minutes to 5psi and wait. If pressure doesnt drop on either test I consider that a pass. No amount of tuning will compensate for an air leak and if you have one you wont ever get your bike in tune. If you have an airleak buy a tube of Hondabond. That stuff is gold for sealing up engine cases.

Second step is just general engine health stuff. I would take a compression test and make sure you dont have any issues there and record that info for later diagnostics. I would also do a squish test, gear oil change, complete carb soak and clean, air filter clean and general cleanup of the entire scooter. Once you are done with all of that I think your into tuning territory.

I have siezed one too many cylinders (just one FYI) from poor tuning practices. Now (unless I am using my SmartCarb but thats a different story) I start with the idle circuit and get the scooter idling OK and responding to throttle blips quickly and cleanly. After you get your idle dialed in I tune WOT throttle performance. I start with a comically large main-jet and work backwards until WOT cleans up and rides OK. From there you jump into needle position.

As for temps I agree that 370F is too hot. I am going to guess you have an airleak creating a lean condition and that needs to be fixed before you start digging into jetting behavior.

[kosmos]

Well, I couldn't get my stock carburetor to tune right and it got either too hot or wouldn't go down the road. Maybe its carb tuning inexperience since I always ever when I started modding had problems.

I wouldnt think I'd have an airleak. I've tested this bike and the only change I did was put on the bore kit. It should still be good. My problem before wasn't even detectable with a pressure leak down test, I think it would of taken a vacuum test to find it. It was the oil pump plug I bought that wasn't engineered in my opinion right. It doesnt use the same method of sealing as the stock oil pump does, I dont like it. and mine since ive seen them used before, may have been a dud. Everytime I pulled it back out, no amount of lube of any kind would stop the rubber o-ring they used to seal it from splitting. it was a tight fit to go in and that was splitting it. Once replaced it back with the stock oil pump, and had to hook all that back up, thats what kept me from doing it, the bike became tunable. Just a little carb going over and everything worked.

I got it running stock just fine, no overheats, no cutting out from the throttle.

My arreche carb now runs, no cut outs from an idle to wot but, its hitting 370ish when I keep it floored on a 3 mile straight stretch. I can upjet but I felt like it ran better with the smaller main jet. The arreche isn't that tunable, not much choice in needles or pilot jets. I do thou have a 21mm phbg and since im only getting 33mpg and 55mph, I was thinking about swapping it.

A compression test would probably be a good idea for keeping track of how it was at first. the squish, I just tossed it on there. If there was a base gasket leak from putting the cylinder on, it would be real noticable. But its also a paper gasket so its hard to mess those up. I had a kit with a metal base gasket, and I scratched it one day putting the head bolts in and it leaked. Real noticable. WHen I came home i took it off since it was the only thing i had done and there was a scratch mark from one side of it to the other. replaced the gasket with paper until i could get another metal one.

I mean my squish should be the same as everyone else who has ran this kit, maybe theres a dud out there but, if my compressions good then maybe that ? means its ok. or nothing to worry about, idk. I just don't want to mess with that o-ring gasket that comes on a malossi much.

Ive kept my carbs cleaned and the ones im using now have been in storage and cleaned when I last used them so, they should be good. Just changed my gear oil, and was about to clean the air filter When I got through with .. doing a gear swap. Once I am happy with the carb, mayhbe thats something I should do now to get my tuning consistency, normalized.

Since I made thsi topic ive got the idle to WOT cleaned up and only have what is going on, at wot after 3 miles im at 370F. So maybe try the larger MJ and see if everything still runs good. I hate going through that tuning. But I got a lot more experience now that I've went through this once. This is the last little change I'm going to do with this carburetor

For reference, im running the 15PJ, the leanest arreche needle (they sell 3) at the leanest clip setting, and a 92.5MJ RIght Now if my memory serves me correct. probably will change back to 95 in the future. if gas mileage worsens, may make me change the carb too. Don't know if it will be any help though.
is 30mpg normal for a sport setup like this and aftermarket 17.5mm carb or even anything else like 21mm?

[hippo008]

You make a lot of reasonable points.

I would say just one thing to all of that. Trust but verify. I have had all sorts of stuff go wrong because I didnt do my idiot checks from brakes failing, engine siezing, axle bolts coming loose, you name it.

If you are sure you dont have an airleak or some sort of weird timing problem, just make sure youre running the appropriate spark plug temperature for your setup and start slowly increasing main jet size until things cool off.

[kosmos]

Done a couple of things to the bike. I changed air filters, 17205-GAH-000 for anyone running the af28 super dio (I think) airbox.

(one of these)
I regreased one of the front wheel bearings by pulling the seal off, the other one I'd need to probably replace the seal too to get to it. Here's the video I used to figure this out with

So I swapped carbs to the PHBG Dellorto 21mm with a 21mm spigot type BGM manifold. When I first put it on, I had much harder pull up to 1/4 throttle especially on 1/4 throttle. Then it bogged up to 3/4 throttle when it would go again. I had trouble keeping it idling and I had figured my pilot jet was rich, because it would not stay idling and it wouldn't cut out when I revved back the throttle. When I leaned the pilot jet, the bike would cut out and I couldn't keep it from doing that until the mixture screw was like 4 turns out. So I went and changed the pilot 1 step richer than it was where I started and it idles fine now without any cutting out when I rev the throttle back. Mixture screw is at 2 turns or something out.

Temps are creeping up to 370 on me on long runs, so I am needing to tune the main jet. But I was wanting to fix the mid throttle bogging. I had went with first, the usual W7 needle. Found my 1/4 jetting right off the bat. You can track where to put your needle clip with Dellorto's needle chart.

So I adjusted from there, setting my taper setting to leaner. I went all the way to the w25 needle, all the way up at the top clip. For comparison, the W7 has a 1.4mm taper and the W10 has a 1.8mm taper. Still had bogging but it ran better.

Checked the dellorto manual and read that mid throttle is changed by the atomizer tube.



Changed from the stock 262au atomizer to the 260au and mid throttle now has some good power. Made a couple of comparison videos to show atomizer tuning changes.
streamable.com/avm3kf
before with 262 atomizer
streamable.com/g0vlmv
after with 260 atomizer

So, I just wanted to keep the same main jet in it to keep things consistent so I could tell whats affecting what and that some other change didn't do anything. you can tell the full throttle is sort of crappy but it gets me to 50ish mph. Will adjust it later and see if I get any changes. And the roller weights seem to of went to far, I went from I thought i had 8.5grams in it but I had 8, i went to 8.5 and I got higher top speed, then I switched to 9gram and I think my overall top speed has dropped, uphills more especially, and my top speed didn't change hardly any.