Should I be afraid to open my scooter up?

[johnny248]

Anyone who has followed any of my build log will know what I have going on, otherwise it's in my Sig.

I am on my second full tank of fuel, and my hour meter shows 4.3 hours of actual run time.

For some reason I am very nervous about opening it up and running it wot.

I'm not sure why, but I keep having this nagging feeling like something is going to go wrong. I don't know if the engine is "broken in" enough, and I'm not extremely confident in my carb tuning. I stuck a 118 main jet in it, it has a 42pilot, needle didn't change, and clip is in the middle position.

Right now it runs about 50mph at maybe a little more than half throttle. I have noticed that I will see Temp's around 350┬░ when running a little harder like that. Don't know if the temp will level out or stay cool once the main kicks in and adds fuel.

G9 recommended running easy on the first two tanks and let it rip on the third.

Should I keep riding around this tank at 1/2 throttle, or simply go for it and see what it will do? Am I being over cautious with it? I just seem to have the luck that if something can break, it will.

Then on top of that, I worry about things like air leaks that could cause it to lean out and detonate, even though I don't have any real evidence that there is a problem.

Am I being crazy?

[patthesoundguy]

Nothing wrong with extending the break-in a little longer and making sure its tuned right. You did dump quite a bit of hard earned cash in to a cool build. You aren't crazy BTW. If it were me I'd want to be running at around 350f at full on WOT. That's just my preference.

[johnny248]

That is what I am thinking. I don't want to have to spend the money to replace a cylinder kit, or even more before I ever get to enjoy it. I just dont know at what point I will feel comfortable at wot. It is difficult to tune though if youndont run it wot though...

[curtis966]

Run it bro. If temps start to raise quickly just slow down. Mid throttle temps can't always tell you what your wot temps will end up being any way. I prolly only had an hour of good brake in on my af05 polini bore and went all out after that never had a problem and I saw a few temps over 400 during my tuning. Settled them at about 380 and she ran like a champ.

[Rip_City_Spree]

Take your time if you don't feel ready to open her up yet dont. Keep an eye on temps. And just keep pushing it harder and harder till your comfortable going WOT. If you did your heat cycles and are working on your second tank I think you'll be fine but I know what it's like. When I got my cobtrssa and felt it was running great and put on a few hundred miles I went to start it and blew a piston clip. Sucks but it happens even if you think it's good to go. Just keep a good eye on it and keep temps low and you'll be fine

[johnny248]

I had the 108 in it, and just switched to a 118 to see how it changed with the wot from a stop bog it was doing. When I tried the same thing with the 118 it actually stalled. It was just an experiment.

I am running 32:1 , along with an NGK BR8HIX plug.


As far as the temps go, I'll have to pay more attention to it. I want to say it was fully warm idling around 180ish or so, and then while driving around in the 30mph range it was mid to high 200's. I haven't actually rode on flat land at wot throttle yet so I don't know what it will be doing there.

I'm not sure what could be leaking if anything for an air leak. I was pretty careful putting my intake manifold together, and torqued all of the fasnteners related to it to the proper torque spec for that size bolt, except for the carb adapter because it smashes the rubber down.

The whole thing is a little frustrating since I am trying to ride this thing with what we assume are too light of clutch springs.

I suppose I could redo the manifold and use a gasket sealant on all of the gaskets. I don't know what else could be leaking if anything? Can the exhaust pipe gasket cause issues? I was looking to see if I could find another gasket to use instead of the exhaust packing ring. I was thinking using that packing along with a flangle style gasket. I've see some listed on eBay, but haven't had a chance to take measurements to see if they are correct.

[DeanP]

A quick way to tell if you have any air leaks around your intake is to spray some ether about it and if the rpms rise, you know you have a leak. We do this for snowmobiles around the crankshaft to see if crank shafts seals are good or not.

[johnny248]

OK, as you said G9, I went on a little straight away and opened it up. It still has the 118mj in it. I stopped it when it hit 398┬░ ,wide open I was seeing 95xx-99xx rpm, and 55mph on the GPS.

So something is wrong. Someone else asked about this carb staying tight in the adapter boot. I just noticed that mine is not as tight as I though it was. I can wiggle it bacmand fourth, and could prob pull it out if I tried. When I attempt to tighten the clamp anymore, it just skips a tooth and backs loose again. I am going to try putting a better clamp on there. I'm not sure if that could or would have any effect on the temps, but I guess address any and all issues to you see.

What is my next step if that does not change anything?

[Wheelman-111]

Greetings:

If the clamp was stripped and the carb loose, fixing it surely will improve the temps. You will probably have to retune the carb to the new reality.

[whitey]

The carb should not wiggle. If you can pull it off with one hand there is a problem. Sometimes the hose clamps you get with intakes are weak and strip out easy. If it is skipping gears it's broken, take it off and throw it away. Go to the hardware store and buy a couple new stainless steel ones. It should have angled slots in the band where the threads catch. Also, everyone should wipe the oily gas off the rubber and carb with a rag with brake cleaner or similar to remove any slippery residue that would make it easier for the carb slip out.

[Rip_City_Spree]

something tells me once you find the air leak you have to down jet that main quite a bit. the first thing I did was swap out the clamps with good stainless ones. I have two on mine as my hose from intake to carb is a bit longer than yours.

[johnny248]

I replaced the carb clamp. s*** around the intake manifold reed cage, carb bolt, cylinder base, and oil pump plug with some carb cleaner and I wasn't able to pick up any leaks. If there was an air leak, wouldn't this have cause problems idling?

I'm going to install the OEM fan also. Right now there is one I picked up several years back from Scooter Assains or something not knowing what I was doing.

My brain isn't function properly know after spending the last 6 hours diag'ing a wiring harness in a VW(don't even get me started) but I am looking at my stock fan , and looking through the fan intake on the bike at the "performance" fan that is on it, and maybe I am completely crazy, but I swear that the fan blade is pitched the opposite direction. Do some scooter engines spin the opposite direction? Maybe this doesn't make a difference, but is it actually possible that the fan is going the wrong way????

[Rip_City_Spree]

It could make a difference Id say if the og is in good shape give it a go and see. Of that doesn't help try down jetting and see what happens. Is you pipe clear? That would be the next place to check.

[johnny248]

I am going to install the factory fan and see what happens. I will end up kicking myself in the head if that was causing me problems. It may also explain my my Taiwan kit on my last build blew up?

The only reason I put the 118 mj in was to make a drastic change to see exactly what it did in order to give me a better idea of how my bike is running.

Here is the "performance" fan next to the stock fan. Again, I don't know if it matters in this case of a cage fan, but I can tell you for a fact that if this was my boat, it would be moving backward through the water unless I switched the rotation direction in the outdrive.

[Rip_City_Spree]

Looks like your OG seen better days too. Hope that's it bud. hondasan did things for a reason could be it needs to be moving the air a certain direction for it to cool properly. Hondasan works in mysterious ways.