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Post by 90GTVert on Nov 12, 2020 23:06:22 GMT -5
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Post by captincvmn on Nov 12, 2020 23:20:38 GMT -5
Well that stinks. I kinda want to say that’s enough mileage from a high end setup but I’m not sure. I guess we always want more. I would say from what I’ve seen that you have gotten your money’s worth out of that.
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Post by 90GTVert on Nov 12, 2020 23:56:12 GMT -5
Well that stinks. I kinda want to say that’s enough mileage from a high end setup but I’m not sure. I guess we always want more. I would say from what I’ve seen that you have gotten your money’s worth out of that. I don't think the flaking is a huge loss at this point. I didn't price it out, but assume roughly $100 for a C or D piston, plus the 4-6 week wait. I thought maybe I'd be able to stretch it out to 3,000 miles if I got lucky. I think everything would last longer if it weren't revved so high. I probably could have racked up more miles riding around with the Peace Pipe at 10-11kRPM or even with a pipe good for about 12k as some suggested. Part of me is disappointed, part of me isn't. It is a hard running engine for what the whole engine kit costs. I've had the cylinder for roughly a year. I have put nearly the mileage that this kit has on it in just over a month before, so it certainly wouldn't be a good cylinder for regular riding and commuting many miles. If you want more of a toy, it's cheap compared to some choices and there's definitely enough power to have some fun with. Unfortunately, I don't have much experience to base my opinion on with this type of kit. Multiple people tell me the quality sucks on the TPR and get a better kit. You see that even here on the forum. I'm so used to Taiwan iron bores and having to port/adjust everything to get strokers to work out that it all seems pretty good to me to be able to bolt on a kit that makes 20HP that meets it's specs for the most part. The head could use a redo IMO and the squish clearance is about 0.3mm too wide out of the box. I assume the squish is a safety margin for people that won't check it and some people that have watched my stuff about the head don't even see why I worry about it. BTW, this isn't the end of the TPR totally. Just this particular cylinder. I still have the newer one with 281 miles on it so I can put that on and see if I can bust a belt or not.
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Post by Lucass2T on Nov 13, 2020 3:31:46 GMT -5
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Post by oldgeek on Nov 13, 2020 6:43:43 GMT -5
Do you think the crank is ok with all of that hard nic floating around?
Rough calculations say cost of kit per mile of fun is at least $.25 I guess that's not so bad.
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pewpew
Scoot Enthusiast
Posts: 254
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Post by pewpew on Nov 13, 2020 7:07:48 GMT -5
The good news is; I don't have to measure the cylinder. The bad news is; the cylinder is finished at 2,138 miles. There was a small chip at the bottom of that large flaked off area, so I'm guessing it started there. The piston is scuffed in that area and has cuts in the crown. It kinda feels like something is stuck in the crown in 1 or 2 spots, so I guess some Nikasil plating is in there. I think the head mod worked so far. Kinda looks like it leaked if you look at the head, but if you look at the cylinder deck you can see separation of the o-ring areas. The edges of the piston crown don't have color and have a mildly rough feel, mostly near the exhaust. I guess it could be coolant, but it could be detonation or I'm running it a little lean. I have been running more lean needle settings than ever before because it makes the throttle response very crisp, but I won't hold it at mid-throttle positions with it leaned out. Sadly i called it yesterday that it would look like this. I had the same thing happen to me once. Too much ignition advance or lean condition
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Post by Lucass2T on Nov 13, 2020 7:27:49 GMT -5
What does the kinda 'faded' washing pattern on the crown mean? Out of curiosity I looked up piston flow/wash pattern pictures. You often see theres a very defined line between the carbon buildup and washed area around the piston's crown. With your piston the washing is faded and there's not really any buildup. I know I am comparing MX and racing engines which are run WOT all the time with a street ridden machine. Maybe John can explain a bit more
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Post by 90GTVert on Nov 13, 2020 12:20:42 GMT -5
It doesn't seem like it would be worth it to me. I just looked at a couple of sleeve model #s and they're $80-100. So say $200 for supplies (sleeve, piston kit, gaskets/o-rings). I've never even seen a sleeved cylinder in person or paid any attention to them, but I'd have to imagine you'd want the bore to be pretty true before it goes in. Not sure if it has to go to the point of a pro machinist and honing and all. The head may need to be redesigned. Sounds like a lot for a 77cc that prob runs almost as well as it used to. I guess the big advantage would be once sleeved, you can re-sleeve easier? Still, there goes that $200 in parts again, even if no machine work is needed. Honestly, I would think it would be more worth considering this sort of thing if you had a really good cylinder. It all worked great, but the bore is toast. Even then, the first page that came up with a search is linked below where they say they could strip, bore, plate and hone for $243. Seems like everyone says re-plating isn't worth it and you just junk the cylinder in the scooter world. www.usnicom.com/plating/pricingI'm not against custom stuff and putting in some effort, but I don't know that any of this is the best option for me here. Do you think the crank is ok with all of that hard nic floating around? I'm gonna take a look. Not planning on a full teardown though so it will mostly be the most obvious check and listen/feel and call it good enough after a little flushing. Too much ignition advance or lean condition I'm not totally sure what to make of it TBH. I still think the first time was at least partially due to coolant. You can find info from Eric Gorr about coolant doing exactly what I experienced (erosion on the edges of the crown and then the ring sticking). I actually added more ignition advance after that, and the piston has looked better than before. The first time around I was running it more rich and now it's leaned out part throttle, and again the erosion isn't as severe as it was. I don't see peppering on my plugs whenever they come out. I have heard a little knock before at certain throttle positions, but I haven't noticed since I put a larger main jet in there and I just don't hold it at say 1/2-3/4 throttle much at all since it's been leaned out.
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pewpew
Scoot Enthusiast
Posts: 254
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Post by pewpew on Nov 13, 2020 13:31:55 GMT -5
It doesn't seem like it would be worth it to me. I just looked at a couple of sleeve model #s and they're $80-100. So say $200 for supplies (sleeve, piston kit, gaskets/o-rings). I've never even seen a sleeved cylinder in person or paid any attention to them, but I'd have to imagine you'd want the bore to be pretty true before it goes in. Not sure if it has to go to the point of a pro machinist and honing and all. The head may need to be redesigned. Sounds like a lot for a 77cc that prob runs almost as well as it used to. I guess the big advantage would be once sleeved, you can re-sleeve easier? Still, there goes that $200 in parts again, even if no machine work is needed. Honestly, I would think it would be more worth considering this sort of thing if you had a really good cylinder. It all worked great, but the bore is toast. Even then, the first page that came up with a search is linked below where they say they could strip, bore, plate and hone for $243. Seems like everyone says re-plating isn't worth it and you just junk the cylinder in the scooter world. www.usnicom.com/plating/pricingI'm not against custom stuff and putting in some effort, but I don't know that any of this is the best option for me here. Do you think the crank is ok with all of that hard nic floating around? I'm gonna take a look. Not planning on a full teardown though so it will mostly be the most obvious check and listen/feel and call it good enough after a little flushing. Too much ignition advance or lean condition I'm not totally sure what to make of it TBH. I still think the first time was at least partially due to coolant. You can find info from Eric Gorr about coolant doing exactly what I experienced (erosion on the edges of the crown and then the ring sticking). I actually added more ignition advance after that, and the piston has looked better than before. The first time around I was running it more rich and now it's leaned out part throttle, and again the erosion isn't as severe as it was. I don't see peppering on my plugs whenever they come out. I have heard a little knock before at certain throttle positions, but I haven't noticed since I put a larger main jet in there and I just don't hold it at say 1/2-3/4 throttle much at all since it's been leaned out. The plugs dont really show anything with unleaded gas, my plug doesnt even get color with a rich mixture. Looking at the piston it has melted on the exhaust side which is caused by a lean condition
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Post by jackrides on Nov 13, 2020 13:44:32 GMT -5
There are apparently reputable companies that will refinish/replate nikasil cylinders.
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pewpew
Scoot Enthusiast
Posts: 254
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Post by pewpew on Nov 13, 2020 14:16:12 GMT -5
There are apparently reputable companies that will refinish/replate nikasil cylinders. Not worth using 250$ to replate a cylinder that you can get brand new for the same price
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pewpew
Scoot Enthusiast
Posts: 254
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Post by pewpew on Nov 14, 2020 8:02:16 GMT -5
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Post by 90GTVert on Nov 14, 2020 8:45:47 GMT -5
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Post by 90GTVert on Nov 14, 2020 15:28:14 GMT -5
Figured I'd tell you guys how dumb I am. I know, that's old news. I flushed the cases out with premix. I spilled a little in the floor on the first try. 1/2 cup... maybe more. Soaked it up with kitty litter when I was done. I keep a gallon jug of water around for whatever arises since there's no running water in the garage. Decided it would be a good idea to dump that on the floor and clean it up, hopefully removing some of the fuel smell that lingers and making sure nothing is slippery. The anti-fatigue mats that stay by the bench were moved out of the way. I saw something else that I wanted to move, so if water ran too much (garage floor has a 5 degree slope so water heads toward the doors) it wouldn't get wet. Stepped on the mat that had water between it and the floor and busted my ass on the concrete floor. Hit my butt and lower back mostly. The knee that I broke in a crash hurts now, lower back hurts, hip hurts. I think all just from the immediate tension and twisting when you try not to fall and the knee never feels good anyway. I'm fine. Dumped some more water down and finished cleaning the floor. May not work on the scoot anymore today. I'm definitely letting that stuff dry thoroughly before I go back out there.
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Post by yambw’s on Nov 14, 2020 16:00:18 GMT -5
Hi I’m new here hope you get well soon! Just wanted to make my self known I joined after watching many of your videos on YouTube
I have Learnt a lot form you and your projects while building my own project at the same time
Hope I can be a help to the forum as well as being helped I have 20years Experience with scoots and still learning
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