Missing stainless reed petal. Rebuild engine?

[Req]

So it seems I sucked up a stainless steel reed petal. I checked the compression before I pulled the intake and both cylinders were even. Engine was not making any noise other than running a bit rough due to the reed. What is the common practice when this happens? Should I yank everything and make sure its not floating around in a transfer port or something? I would think stainless could do some damage if it already has not.



I have a set of 760 reeds I can install today if I have nothing to worry about. Thanks for the help.

 

[Big Kahuna]

pull the top end. dont take a chance, may have gotten spit out or wedged in the bottom of the cases.

 

[Mike W]

Before I went any further I would try to find that broken reed like BK suggested. If it’s in the cases it will eventually get spit out and probably take out your motor in the process.

 

[Req]

Im going to take this opportunity to swap cases since I have to pull the top end. I have 760 cases and a better crank I am going to build over the weekend with fresh crank seals. I have a nice bore 62t cylinder and pistons if I find damage in my 61x cylinder. You guys are right, I was in denial, lol. In the future I will be running epoxy/carbon based reeds. Im assuming sucking one of them up is not as big of a deal.

 

[mikidymac]

The fiber reeds won’t hurt anything.

 

[OCD Solutions]

I had this happen on my old SN so I tore the whole motor down looking for it and never found it, nor any evidence that it went through my motor. On re-assembly, I found it on the high side of the reed cages wedged up in a corner between the cages and the carb plate.

Like you, I had work I wanted to do anyways so it was a good opportunity to rebuild. However, just because it's missing, it doesn't always mean it went downstream.

 

[Req]

I put together a 64x crankcase assembly I had extra as well as a practically new crank with new seals. My love of plum crazy is apparent Im sure. My second pulse fitting is missing. I dont need it now but may in the future. How would you block it in the interim? JB weld or could something less permanent work?

Additionally I discovered that my timing was retarded by about one degree by the previous owner on 62t electronics. Should I set this to 1 or 2 degrees advance for a bit more braap?





Thanks for the help!

 

[Vortex]

You can use a vacuum cap or a PC of fuel line with a tight fitting bolt wedged in it on the UN used pulse line. If you're worried about a leak just pressure test the engine to make sure.

It's common to advance the stator timing for freestyle riding, if you have an msd enhancer this can put you closer to almost 30 degrees down low if you set it to the 5* advance mark. Just be aware it's gonna have a lot more timing at high rpms as well which is not what you want generally speaking

 

[Big Kahuna]

You can use a vacuum cap or a PC of fuel line with a tight fitting bolt wedged in it on the UN used pulse line. If you're worried about a leak just pressure test the engine to make sure.

It's common to advance the stator timing for freestyle riding, if you have an msd enhancer this can put you closer to almost 30 degrees down low if you set it to the 5* advance mark. Just be aware it's gonna have a lot more timing at high rpms as well which is not what you want generally speaking

"My second pulse fitting is missing"

Npt gonna do any good to use a vacuum cap or hose with no fitting..

 

[Vortex]

Ok ok ya got me.

Get a new fitting and then cap it if un used. Better than jb weld etc

 

[Req]

Ok ok ya got me.

Get a new fitting and then cap it if un used. Better than jb weld etc

Where would one obtain the fitting and what is it called? Is there a cross reference I can use to get it at the auto parts store? I have some in other cases but Im not sure how easy it would be to remove it without damaging it.

 

[Big Kahuna]

You should be able to find a new fitting st a hydraulic supply shop. Either press in or you could get a threaded barb or plug. Just tap threads and install. Not sure what size.

 

[DAG]

Pulse fitting is a $3 OEM part. Don't cheap out

62T-14251-10-00

 

[Req]

Pulse fitting is a $3 OEM part. Don't cheap out

62T-14251-10-00

Ordered! Thanks for the help.

 

[Req]

So I finished tearing the original engine down and it seems the reed had a fun time with the top of my piston and a bit with my dome. The dome I think is fine, the piston however has baby slivers of reed sticking out of it so its toast. Oddly the bore seems decent.

I find myself with a decision I was hoping I could get some help with. I have a decent bore with matching pistons 62t setup that is .0 over. I was planning on eventually porting this cylinder and boring it to 83mm over the winter however decision time came quicker than I expected.

Should I run the good compression 62t cylinder and pistons to finish the season or punch it out now and put fresh pistons in?

Here is the damage to original piston and a picture of the bore.




Here is a picture of the spare 62t pistons and cylinder.





Some concerns I have are if I can get the 650 manifold to seal on the 62t cylinder as well as if I am propped correctly for the 62t porting. I have a Concord big hub 9/15, coffman sizzler and 37cc domes. I have felt like I could move the powerband up a few hundred rpm and be happier however I may be wrong.

This has proven to me that just because you have good compression doesn't mean that you dont have carnage.

Thanks for the help!

 

[OCD Solutions]

Funny you say that last part, prior to tearing mine down for the missing reed, it was running strong with good, even compression. Meanwhile; the pistons were scuffed and scored badly enough that I was amazed it was still running at all.

The rebuild never seemed as strong either but knowing what I know now, I am pretty sure I retarded the timing by 3 deg when my intention was to advance it.

Only you can answer that first question. If it's going to be a week or two to get it bored and that could stretch into 3-4 weeks, I'd probably hedge my bets and get it back up and running on the spare cylinder just to make sure I'm not sitting out the rest of what is probably a short season already.?.?.?

 

[Req]

Funny you say that last part, prior to tearing mine down for the missing reed, it was running strong with good, even compression. Meanwhile; the pistons were scuffed and scored badly enough that I was amazed it was still running at all.

The rebuild never seemed as strong either but knowing what I know now, I am pretty sure I retarded the timing by 3 deg when my intention was to advance it.

Only you can answer that first question. If it's going to be a week or two to get it bored and that could stretch into 3-4 weeks, I'd probably hedge my bets and get it back up and running on the spare cylinder just to make sure I'm not sitting out the rest of what is probably a short season already.?.?.?

If I got the ball rolling now I could be out next weekend, possibly. However I look at it I am going to be waiting on an ADA oring kit and manifold gaskets now. As far as the boring I think I can get it done early next week when the pistons come in. My machinist is slow at the moment and he owes me some machine time for helping around the shop.

Do you know much about the 62t exhaust manifold alignment to a 61x ported 650 manifold? Would I use the 62t or the 61x gasket?