midlifecrisis

So Ive got a few pictues to share with you guys. Warning, these are nasty, not for the faint at heart. It appears as like a roller bearing is stuck into the top of the left piston dome, but I cant figure out where it has come from. I know the vitos crank bearings are a lot bigger than what this guy is, it looks more like a wrist pin roller, problem is, Im not missing one. Anyone got any ideas of where this has come from other than the piston wrist pin? Inever checked the pipes before I reinstalled them. I just installed new crank, rods, pistons, cylinders, head etc..... so????????? http://s752.photobucket.com/albums/xx162/amidlifecrisis/Bashed%20piston/

Looking for a set of domes for my vitos hemi head? It has the tabs removed, so those of you in the know, know that I can run other dome types as well, Im just not sure which brand? Let me know if you have some and I can check it out.

OK, so I pulled my pistons out, and all of the needle bearings are intact on both sides, so I called the distributor here in Canada for Vitos and he told me that the bearings on the crank for the rods are 4.5mm, so the one thats stuck in the top of that piston, (if thats what it is), is only 3mm (the same size as the needle bearings for the piston end). So I checked the bearings that came out of the previous cylinders before I switched to this set, and all of those bearings are there as well. So now Im really stuck as to where it might have come from? Anyone else got some ideas? The previous pistons also seem to have a much tighter fitting ring as well? Also, what could be causing the premature wear on the pistons? Im assuming that even tnhough the cylinder sleeve looks and feels fine, that I should have them honed out before I proceed? Thanks in advance for any help!

not sure if the noise is coming from when you kick it, or when its running, but I do knoiw from personal experience that the kicker bushing , and the crank bolt have given me issues in the past, causing weird symptoms and sounds.

Ive never heard of them. Some of the more popular ones are pro design, mod quad, vitos etc...these are tried and tested alot here.

Im with Bubba. The stock size is 64mm, maxed out you can go as high as 66mm, meaning that a stock head is good up to 66mm. The 68mm is (I believe) the stock size for a blaster. On the other hand you can run an aftermarket head (like me, I have a vitos head on a 65mm bore) from stock up to 66mm, when you need a rebuild, it will be time for a cylinder resleeve, but you still use the stock or aftermarket head even after that.

So whats causing the wear on the skirt? Its only been in the bike for 5-10 minutes? I ran it at 20:1 (blue marble premix, w 93 octane, 20 cc domes) for the first 5 minutes as a break in mixture, I didnt get the cylinders honed out when I bought them, but the pistons came with them as a set, and they were visually perfect.? I tell you though that the issues are starting to take their toll. I know theyre my fault one way or another, but enoughs enough. I just wanna ride it

Here are the photos of the piston and head. I found the ring locator pins that you guys were talking about, but this culprit is way bigger, as you can see it is still stuck in the top of the piston in front of my finger. http://s752.photobucket.com/albums/xx162/amidlifecrisis/Bashed%20piston/

Youre kidding! I thought it was something that had somehow come loose from the carbs and got sucked in! I remember looking for the locators on the pistons when I located the rings, but I had no idea that they were an item that would move? They can come loose like that? I will post pics tomorrow.

Actually, I took it apart tonite, and found some pretty serious damage on my left piston. Almost like something was bouncing around, then I noticed a small dome sticking vertically out of the piston. It is a small dome like 3 mil diameter 5 mil long and it looks like steel, versus aluminum, its almost like a nerd candy in steel. Anyone have any idea where this might have come from?

Like I said, Im looking to buy a set of 20 cc domes for a vitos hemi head. Anyone got a set?

If a trued and welded crank has all of its components welded together, how are you to take them apart to replace a rod bearing, or is that the idea?

Stock carbs are 26 mm Mikunis, also if you arent a fan of the twist throttle, Ill trade you my stock thumb throttle for it? PM me if youre interested? As far as oil is concerned, you are going to get a tonne of responses on which oil, premix, coolant etc.... to use, its a touchy subject! If you have one you like, use it, but most of these guys have a preference. Alot use Klotz as there premix (I use bluemarble), most use ATF or a mixture of 50/50 ATF and motor oil (preferably a synthetic) in their cases, and coolant, as Zilla said run the engineice if you want, but regular 50/50 prestone is fine as well.

How much for shipping to L1N1B2 Canada?

Finally got the bike back together 2 weekends ago. Went out to ride the first weekend, and started her up, but much to my dismay, we found that there was a major oil leak from the countershaft seal, which was fixed, thankfully before any damage occured. I wanted to thank the members of the forum who helped me with that. Went out to ride last weekend, and although it started out running on both, now it runs only on 1 cylinder. I went for a short ride down the road before we went into the pits, and it sputtered and then hesitated mid ride, and then it seemed to kinda die out on one cylinder. I wasnt going hard on the gas, as I was trying to break it in as per the manual. I took it to a local bike shop to have the thing looked at ( ie carbs out of sync, leak down test etc......) and they have told me that it is running 25 lbs of compression on the choke side and 145 on the kicker side? This is a brand new motor. I have been building it for a while (I wont say how long, as I dont want any grief) . I mean I havent got 5 minutes on the engine? My mods are Vitos crank, vitos rods, wiseco 64.50 mm pistons, ported cylinders, vitos hemi head, procircuit pipes. I know low compression is a bad thing obviously, I know I will be removing the cases again to look for any signs of shrapnel, but any help on posible causes would be great, I just want to ride!

I have found a bolt that was it seems never installed when the cases were put back together, is this the reason for my low compression results? What is ideal compression for a new rebuild?

Done deal guys, countershaft seal sprocket side was the culprit!

First thing you do is buy a manual. It is the bible, and is worth 10 times its cost. As one of the other guys said, does either piston move when you rock it back and forth in gear? Do not force it though, as more damage may occur. I had exactly the same symptom happen last week after running my brand new engine for only 30 seconds. Mine was the kickstarter gears not meshing correctly. The first time, when I bought it, I thought it was seized, and I found the connecting rod bearing broken into pieces and in under the crank against the cases. This was stopping it from turning, once again, giving the appearance of being seized. There are a lot of things to check before a rebuild if it doesnt need it. I was only patient enough to wait to see the first photo, but it is hard to tell anything from it, as it looks like any other shee top end. Are there any pieces missing from the top of the pistons? Maybe a ring that is evidently lodged? Hopefully this helps

I was lucky enugh for my bike to have come with the pro circuits, and I gotta say that I love the sound and the performance. Do your self a favour though, and make your first purchase for the bike a Haynes or a Clymer manual, it will become your bible for sure. Stay away from the boost bottle, it will rip the carb side of your intakes and lean your bike out without you knowing it and possibly KABOOM, nobody wants that. Oh and X2 on the good luck with lightly modifying it, its addictive alright.

Anyone ever heard of ARTRAX MXT tires? They have a 5 star rating in every category , 6 plys, aggressive tread pattern etc..... and Im wondering if anyone has had any experience with them? http://www.motosport.com/atv/index.php

Here you go, hopefully it doesnt turn out tiny? pm me if you want better pics

Im looking for a member that will pm me back when contacted, if this is you then I am looking for a twist throttle and cable setup for stock carbs. ORRRR I have a motion pro twister already, if you only have a cable for sale?

I think AdrenalineJunky also had one for sale?

I will check with my old man, he now lives in the philippines, so it might take a few days to get back to you. He is a metalurgist by trade, and did polishing for years. If anyone knows a good setup, he'll know

I questioned how realistic that stat was too, but thats what they said to him, I get what your sayin though.