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Post by drawkward on Jun 28, 2011 11:05:58 GMT -5
Where there is a will, there is a way. |
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Post by drawkward on Jun 29, 2011 21:11:37 GMT -5
Was unable to remove the broken bolt, and in the process I ruined the cylinder. The exhaust stud tap is completely over drilled, and I don't have the skills to fix it.  Getting quotes on cylinder replacements. This sets me back on my pipe. What a lousy week for me. It's true what they say, at least for me. When it rains; it pours. Riding around with an open header until I get the new cylinder. Fun stuff. |
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Post by 90GTVert on Jun 30, 2011 8:37:01 GMT -5
I'm guessing you can't weld it up completely and redrill and tap a new hole?
Don't ride for too long with an open header. I did that on a 70cc once (just the front header tube of an MRP pipe, about 6-8" long) and I think it damaged my hearing in one ear. It was funny at first, but 20 miles later I had a headache and my hearing in that ear was screwy for a couple of days. Not to mention the cops and neighbors are going to notice you.
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Post by drawkward on Jun 30, 2011 17:44:51 GMT -5
Not completely open, just leaky. I've got the pipe on there, just only bolted with one bolt. And I have to tighten the bolt every few miles. I suppose I could try to just fill it with weld... Might try that first. Got the quote from Carlos - about $80 for a new cylinder shipped.
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Post by 90GTVert on Jun 30, 2011 18:43:17 GMT -5
Good price.
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Post by 190mech on Jun 30, 2011 20:50:37 GMT -5
There should be enough meat to install a helicoil in there!!
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Post by drawkward on Jul 2, 2011 12:58:17 GMT -5
I'm sure there is... I may do the helicoil, or try to fill it with weld. Either way, I've already ordered a replacement cylinder. If I manage to fix this one, it'll be my back up / experimental cylinder. Give me something to try out different timings without too much worry. Going to also order some extra squish/donut type exhaust gaskets, as well as some flat aftermarket style ones.
If I try to fill it with weld, should I use any special type of weld? I have access to two different wire fed welders; a nice snap-on at my buddy's garage, and my cheap Chicago Electric flux. I want to do the weld, so that I can still use stock studs. I hate having to use two different sockets for something like this. It just bugs me.
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Post by 190mech on Jul 2, 2011 17:35:19 GMT -5
Cast Iron is very difficult to weld!Special filler rod must be used and even then it tends to crack next to the weld..  |
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Post by drawkward on Aug 13, 2011 3:57:00 GMT -5
Been busy of late. Moved into a new apartment and struggling with rent from lack of hours at work. Catching up though. Meanwhile, I've been using the scooter as my daily driver, since my cage only gets 6 miles to the gallon (mystery vacuum). Ended up getting a new cylinder for pretty cheap from Carlos. I explained my problem and what had happened. He threw in some exhaust studs for free, insisting that I need them. Used those with some lock washers, and I am now sold on studs. Solid, dependable. Don't even need locktite with the lock washers. Been tuning as I use it. Still haven't found the right tune. I just recently RTV-sealed the outside of my intake (like I said, struggling with rent). Didn't know there was a leak there until I decided to check for leaks with some carb spray. Big one on the intake. The seal worked great, by the way! No leak what-so-ever after. Been adjusting the carb slowly since sealing that intake last week. Had it running pretty lean last night, being careless and running it WOT for too long.While going WOT, I looked down at the exhaust and the header was GLOWING RED, so much that it looked like I had red neons if you looked at the pavement under me. Still running the stock exhaust, which I believe was clogged and still may be. Running very heavy rollers to keep my revs low while cruising 40-45mph. Max recorded GPS verified speed at 52mph with medium strength contra and 9 gram rollers. Slightly worn belt, which I blame for loosing more speed. Thinking a fresh belt would put me at 55mph. Installed new bars as well. Dying to pay for the custom built pipe and let 'er rip! Should have extraneous funds available soon.   www.youtube.com/watch?v=vuecAQJpEm8 |
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Post by 90GTVert on Aug 13, 2011 5:43:30 GMT -5
Thanks for the update. Glad to see the Yamati is rollin' again. I have still yet to see a header glow on a scooter. I've heard some folks with big performance 2Ts like dirtbikes and ATVs say it's normal for them. :scared: I'm surprised you didn't notice anything else. Check that jetting ad pipe as soon as you can. I guess it could be a timing issue too, but prob not likely.
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Post by drawkward on Aug 13, 2011 11:06:34 GMT -5
I was thinking about retarding the timing a bit. I was reading about how it will lessen detonation and allow me to run a lower octane. I'm getting detonation unless I richen it up to where it'll foul plugs and run poorly. I have way over 2mm of squish. I'm really thinking my exhaust toasted or clogged, as I never got it to work well before. I would try another, but all I've got is my gutted and repacked Leo Vince ZX for the 70cc. I need to cut open this stock one and freshen it up.
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Post by 90GTVert on Aug 13, 2011 12:47:56 GMT -5
I'd check the exhaust before messing with timing. I don't think retarding timing is a great idea with the exhaust glowing. Having never seen it, I'm not familiar with it on a 2T. On a 4T, the header glowing often means the timing is retarded too far and the mixture is burning as it exits the cylinder.
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Post by drawkward on Aug 14, 2011 14:55:26 GMT -5
I was glowing again last night. Would a clogged exhaust cause this? Another thought I had was that my cylinder is the 71mm tall 54mm cylinder kit from Autotech355@eBay. I'm pretty sure it is meant to be used with a 45mm stroker crank, i've got the 42. The piston at TDC is below deck, and at BDC it's not clearing the ports all the way. Could this cause a timing issue? Could my lack of compression be causing an issue?
Also, Brent. In your P90 thread you tested exhausts. You mentioned you had a 70cc tuned pipe you could try, but due to the lack of interest and risk involved you opted out. I wanted to see what types of gains you could get if you ran that pipe on the P90. I think I might be able to pull it off since my lack of squish (near 3mm of it). That would help to keep the piston crown from getting blasted too hard by the excess heat coming back from the restricted small stinger and silencer.
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Post by 90GTVert on Aug 14, 2011 15:55:46 GMT -5
I'd think it would be possible to have a clog create a restriction and build heat. Not sure. The funky cylinder setup would cause odd port timings, but doesn't change ignition timing. I really can't see low compression having anything to do with it. The lower compression will lead to lower temps.
I might end up trying the MRP pipe, I won't say for sure. I can see the wide squish clearance helping you just because of the lower compression to reduce heat, not sure it would matter otherwise. The fact that the piston doesn't clear the ports would be a bad thing for heat I'd think. More of the piston would be catching heat from the port.
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Post by lshigham on Aug 14, 2011 16:07:24 GMT -5
The piston not clearing the exhaust port can cause serious overheating problems as more heat is transferred to the piston due to the increased surface area exposed to the gases.
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Getting quotes on cylinder replacements. This sets me back on my pipe. What a lousy week for me. It's true what they say, at least for me. When it rains; it pours. 
