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Re: Tuning help needed... What am I missing?

Posted: Sat May 17, 2014 11:14 am
by LMH
My friend didnt have time but I will myself come this next thursday, I will be driving from St Louis to Billings Montana and driving through KC. Ill try to time it to after 5 so youre off work by then. Well get it running right time provided. And Ill take a look at the prilia. As far as performance parts to bring Ill have to look over my inventory and see if theres anything Im willing to let go. If they had semi hoarders TV show Id be on it.

Re: Tuning help needed... What am I missing?

Posted: Sun May 18, 2014 2:41 am
by spreeinkc
LoveMyHonda wrote:My friend didnt have time but I will myself come this next thursday, I will be driving from St Louis to Billings Montana and driving through KC. Ill try to time it to after 5 so youre off work by then. Well get it running right time provided. And Ill take a look at the prilia. As far as performance parts to bring Ill have to look over my inventory and see if theres anything Im willing to let go. If they had semi hoarders TV show Id be on it.

That would be awesome! Yeah still made no progress on resolving the issue. I've pretty much given up for now. I'm out of ideas at to what it could be...

The Aprilia I'm just not that familiar with. Never had a fuel/direct injection 2 stroke before. I've done tons of research as to what the problem might be but nothing standing out. Could be anything really. They have known issues with the fuel pump, the fuel injector, the direct injector, the fuel pressure regulator, and the air pump. I think I made it worse b/c now it wont even run with starter fluid and would fire right up on it before. Think I've removed the fuel injector assy so many time now that maybe its not sealing anymore? Idk... Putting that one on hold for now too. I move on to project #3 for now.

Re: Tuning help needed... What am I missing?

Posted: Sun May 18, 2014 12:27 pm
by LMH
Starting fluid on a 2 stroke is one of the worse things you can use. It dries out the cylinder and removes any oil that would have lubed the rings to the walls. Theres physical tests but a scanner is best with the ditechs.
If I can borrow Vespa of St Louis' Aprilia scanner Ill get it. No guarantees as Ive only borrowed cheaper tools from them. Two great guys named Eric own Vespa St Louis and I try to promote them as much as possible.

Re: Tuning help needed... What am I missing?

Posted: Sun May 18, 2014 9:52 pm
by patthesoundguy
Ive never ever had any luck with starting fluid. I find a little squirt of two stroke mix in the cylinder or carb works well for me. If it takes off I'm good if not there is somthing else to sort out. Fuel pumps can be strange on those rigs with the control boxes. If all of the ducks aren't in a row the pump won't pump. Hope you get it going :-)

Re: Tuning help needed... What am I missing?

Posted: Sun May 18, 2014 10:54 pm
by spreeinkc
LoveMyHonda wrote:Starting fluid on a 2 stroke is one of the worse things you can use. It dries out the cylinder and removes any oil that would have lubed the rings to the walls. Theres physical tests but a scanner is best with the ditechs.
If I can borrow Vespa of St Louis' Aprilia scanner Ill get it. No guarantees as Ive only borrowed cheaper tools from them. Two great guys named Eric own Vespa St Louis and I try to promote them as much as possible.
I can check for codes through the display. There are no current or history codes. It was carb cleaner actually. I know, just as bad but it works. I don't know what's going on with it now. It's got the brightest spark I've ever seen on anything I've ever checked but yet I can squirt a syringe of premix directly into the cylinder through the spark plug hole or the throttle body and not so much as a sputter. It was running on it's own (barely, for a few seconds at each time) the other day when I finally got the fuel leak fixed and now nothing.

As for the Honda I was out riding it today. Went from a 115 back to a 120 to try and keep temps down. If I'm just putting around the neighborhood temps are around 300. If I'm riding a little faster it's around 350 but any long stents of 80% throttle or a lot of stop and go with WOT It will hit 400. Plus I dont't think it's hitting the max rpms it should be. I don't have a tach but it seems like it's just not quite there.

I'm half temped to pull the head to inspect the cylinder. I rode it around for weeks with the 120 MJ assuming it was fine b/c it acts very rich and goes through gas like it's nothing. I just recently added the temp gage to try to dial it in and that's when I realized its already running too hot.

Re: Tuning help needed... What am I missing?

Posted: Tue May 20, 2014 7:29 am
by patthesoundguy
Remember spark plugs can fire awesome outside the cylinder but may not fire in the cylinder. Did you try a new plug?

Re: Tuning help needed... What am I missing?

Posted: Tue May 20, 2014 7:58 pm
by spreeinkc
Plug is brand new. (although I have had new plugs that were bad) I think I've determined the air pump is bad. Borrowed a gage and tested it and it didn't even move the needle. I removed the pump to inspect it but I can't tell anything by visually inspecting it. I need to jump on the aprilia forum and do a little more research and see if I can determine if this is the problem.

Re: Tuning help needed... What am I missing?

Posted: Tue May 20, 2014 8:40 pm
by LMH
Theres a slim chance its the pump, itll start even if the pump is bad just not idle for anything. Especially with using ether. Hopefully itll be something easily seen but who knows. The pureJet is the better of the FIs for the sr50.

Re: Tuning help needed... What am I missing?

Posted: Wed May 21, 2014 10:47 pm
by spreeinkc
LoveMyHonda wrote:My friend didnt have time but I will myself come this next thursday, I will be driving from St Louis to Billings Montana and driving through KC. Ill try to time it to after 5 so youre off work by then. Well get it running right time provided. And Ill take a look at the prilia. As far as performance parts to bring Ill have to look over my inventory and see if theres anything Im willing to let go. If they had semi hoarders TV show Id be on it.
Are you still planning on rolling through KC tomorrow? If so let me know. I can load it up and take it to work with me if your gonna be here sooner than 5. I've double and triple checked everything I can think of and can't figure it out.

Same with the Aprilia. It might not be the air pump. I'm out of ideas there too. I did get a gage and checked the compression and its around 115. Lower than I'd hope but plenty to run. I'm dumb founded as to how I can add fuel directly to cylinder and can't even get a sputter or nothing.

Hope you have a chance to swing by. Thanks

Re: Tuning help needed... What am I missing?

Posted: Sun Jun 01, 2014 3:58 pm
by spreeinkc
Any more suggestions on what's up with my Honda? I reread this whole thread to make sure I didn't miss anything. It still acts same way.

Re: Tuning help needed... What am I missing?

Posted: Sat Jul 05, 2014 1:37 am
by ped
Wheelman-111 wrote:Greetings:

Although I'd be the first to agree that I am a simple-minded man, most of us are fimiliar with the concept of non-combustible hydrocarbons (oil) displacing fuel causing a LEAN condition if excessive oil for existing jetting is introduced. Extra oil may lubricate, but doesn't Vaporize and so doesn't cool the combustion chamber as well as fuel with less oil in it. Oil-Rich = Fuel Lean. That's why it's recommended to up the jetting when running extra oil, and downsize with less oil.

Once you've settled on an oil ratio, you can jet accordingly. Old outboards (I've owned a few) that ran 25:1 and even 20:1 need stupid-big jets, smoked like a coal plant, and fouled plugs pretty frequently. That's why I'm considering DECREASING from the Forum Cognisenti Consensus of 32:1, which except for abundant smoke hasn't been a problem for me.
Hi wheelman.
for I minute I thought? what would we do with out a knowledgeable person? what oil % are you going with? willing to share valuable information. I run 3.6oz to 1gal. on the 72. is it possible that your considering it? what the hello is the forum going to do? 2oz is a little low for the 72 BBK. we are all in trouble.
Hi spreickc.
I would do a leak test with a hand pump to 6psi. I had similar problem and found a leak on the ct manifold. use soapy water is best. plug your exhaust, and try not to blow out a seal. good luck.

Re: Tuning help needed... What am I missing?

Posted: Sun Jul 06, 2014 12:22 pm
by Wheelman-111
Greetings:

My supply consists of 50/50 AvGas and Pump Premium mixed at 32:1 with Motul Synthetic. The mix doesnt vary with displacement because of the fixed ratio of fuel and oil unlike a pump setup. I used the same fuel withe the Corsa and MHR 72s as I do with the Fabrizi 81cc. I hate to mess with a good thing, but yes 35:1 would probably be just fine. OMC Outboards (liquid cooled) specified 50:1, so the plausible range is broad. Smoke and plug fouling define the upper limit, while lubrication failure defines the lower.

Re: Tuning help needed... What am I missing?

Posted: Sun Jul 06, 2014 1:09 pm
by ped
Hi wheelman. always great advice.
32 to 1 is a great mix. sounds like you are dialed in.
isn't the AV fuel 100% leaded? which is great for aluminum bores. but not too sure on cast iron bores? I would have to take a look into that.
so is there super secret best mix of fuel and oil?
anyone know what those guys goin hundred mph are using?
share the love :love:
so are you going to be in sand between the toes and a umbrella drink, down in Margaritaville?
tourist covered with oil, shrimp beginning to boil. we miss you already.

Re: Tuning help needed... What am I missing?

Posted: Mon Jul 07, 2014 3:48 am
by bobbygerard
Have you tried going lower on the jetting. I run a 86 jet it works doesnt overheat. Runs well. Any higher than a 92 it runs like crap

Re: Tuning help needed... What am I missing?

Posted: Mon Jul 07, 2014 3:48 am
by bobbygerard
Have you tried going lower on the jetting. I run a 86 jet it works doesnt overheat. Runs well. Any higher than a 92 it runs like crap