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So after a solid weekend of thrashing the V let go. It locked up tight and caught my attention in a serious way. So, after much ado I pushed my bike home while reflecting on the fact that about 30 years ago I pushed my first bike home too, except that was a 78' DS 100 and I was merely out of gas.
I pulled it apart in due form and just as I got carbs off I could not help but notice bit of aluminum in the intake runner. Sigh..here we go. I plug and it looked like it had been held against a grinder for a bit, not good, I pulled the cams and one valve appears to have thrown a set of locks, ouch. I pulled the head and well...see below.
I have to say that the V was awfully considerate. after it was done playing around it took all of the bit and pieces and placed them neatly in the oil pan lol.
Rear cylinder. After closer inspection I do not think the locks are to blame. I hastily assumed it to be the case because of the way the valve appeared initially. However, up on closer inspection of the piston on the main fracture line it appears as though I had a slight crack or casting imperfection all along. I say this because the crack follows a casting mark perfectly and there are dissimilar colors of metal within the crack. Typically that indicates an old crack where contaminants have penetrated; I think I may have encouraged that crack to grow with some ham-fisted persuasion. I say this not as an arm chair novice but as a fairly experienced ultrasonic inspector. I recall seeing evidence quite similar in destructive testing practices to verify non-destructive results, especially in cast materials, though usually on welded pieces.
No biggy, it's apart and on the road to recovery. I have a spare set of cases which are being honed tomorrow to fit a set of used slugs while I laboriously clean the transmission. I simply cannot believe how much metal can be trapped in one cassette of gears. Pro tip: if you grenade your engine clean it thoroughly one piece at a time. I guess I'm thankful I bothered to put together a set of heads with new valves and all that. As long as the crank is good I should be all set by new year, possibly February.
The pile I pulled out after the first cleaning. Output shaft cleaned, lubed and installed. Clutch and oil pump were spotless. Main shaft in progress. I take 1 piece off at a time, clean, and reinstall. One gear has a bit of wear, luckily I have an extra. Superb, all things considered.
Im likely preaching to the choir here ......but dont reuse transmission (or any) snap rings and transmission snap rings have a "side" to them. They are stamped, and so have a "sharp edge" side and a rounded side.
Well, I did see some "unexploded ordnance" in your first pic.
Yeah, there's usually a bit of that laying around. I'll make it back to the range at some point...hopefully...if I can ever get this damned engine back together.
Im likely preaching to the choir here ......but dont reuse transmission (or any) snap rings and transmission snap rings have a "side" to them. They are stamped, and so have a "sharp edge" side and a rounded side.
Funny you should mention that. I was just looking them up on babbitts.com, a whopping 10$.
Yeah, there's usually a bit of that laying around. I'll make it back to the range at some point...hopefully...if I can ever get this damned engine back together.
Spent some time at the range today shooting my new .45. It appears it is much like my other weapons, motorcycles, cars, etc. I'm the weakest link.
For peace of mind I clean each bolt, loctite it, torque it, then mark with a paint pen. At a glance I know for sure it's done right. The forks only go one way, make sure they're right or it's coming back apart. Cycle the transmission by hand several times before closing up the cases. This is a quieting gear that the guys on vtr.org say is worth removing for rotational mass savings. 5oz off the main drive gear. RC51 starter gear. The type of wear to look for on dogs. More worn dogs.
Stock motor, aside from reground cams and typical mods. But remember, this was an abandoned bike that sat for 5 years and was stored correctly and when I got it I just started it and hit the road without so much as an oil change. So there's that, and the unknown history of the bike with the PO and what you have what you see in the photos. I stand by the ham-fistedness, loan me your bike for a day and I'll prove it, though I have to agree Honda does usually know what they are doing. You know what they say though, make a better machine and I'll make a better idiot.
Stock motor, aside from reground cams and typical mods. But remember, this was an abandoned bike that sat for 5 years and was stored correctly and when I got it I just started it and hit the road without so much as an oil change. So there's that, and the unknown history of the bike with the PO and what you have what you see in the photos. I stand by the ham-fistedness, loan me your bike for a day and I'll prove it, though I have to agree Honda does usually know what they are doing. You know what they say though, make a better machine and I'll make a better idiot.
AV
As the cams were aftermarket.... and I dont remember you saying one way or another... Was valve lift confirmed? valve to piston TDC clearance confirmed? If so, what was the clearance measured?
I guess from my POV and scant 21 yr roadracing career (so far) a Japanese sportbike can be run to its limit for hours a weekend all season for years with almost no visible wear internally. Yes you can break a bike if you do certain things like over rev it but it would take some doing.
My last CBR600 had 98,000 miles on it including daily street use and seasons of racing. It ran flawlessly when it was stolen at 98k (sadly).
The difference here are sketchy (it seems) engine mods and some possible neglect and non maintenance.
Sounds like it will live again which is good new for superhawkers everywhere.
It is coming back together quite well. The trans is back together and I'm picking up the top half of the block along with pistons and crank on Monday. Once I confirm the crank and block code I can get some bearings ordered along with rings. After I get that debacle sorted I can finally put the TDC question to bed without any reservations in mind. Then..then I can confirm piston to valve clearance which I suspect is just fine but at this point I'd like to know for certain.
Fun fact* The last set of extra rods I had for the V were different by about 30 grams. I thought that was odd so I kept them aside to look at again later in life. Now that I have yet another set on hand I can confirm that despite Honda's typical accuracy, there are some oddities out there.
Oh it'll live again, but inside the V is a fairly low tech combination of cheap parts. It's kind of a miracle it works as good as it does. Either way, this won't be the first or last cast piston give it up under extreme conditions. Hell I had an SRAD 600 once that let go of 2 at the same time in a very similar fashion one fine weekend at Moroso. That bike had no mods, excellent maintenance and a known good service history but absolutely did not hold up to 6 launches followed by full throttle runs backs to back. Talk about an eye opener, 4th gear full throttle, BANG! I let the smoke out.
The Block is a BB, the Rods are B2 and the Crank is a B2 as well. Based on the charts that means I need Brown bearings for both Rod and Mains. I happened to have a set of used Browns around with low mileage so I used them as a reference check to help account for crank wear. That, coupled with a handy dandy micrometer confirm Honda's #'s and quality. Almost no wear at all on a 15K crank.
I started reassembling the new heads last night and all they are as close to perfect as possible, all valves, respectively, being within a shim size of each other. Fortunately, and surprisingly, the RC buckets fit with a much smaller shim then when I mocked them up on stock heads. Pretty much at any time now I can start checking PTV clearance as well as radial. Only down side is that the top half I have has a bit more taper than Honda allows as far as I can tell. Honda says .004, which seems like a lot to begin with, and I measure .005 on the front cylinder. I'm wondering if it would be different with a torque plate, hmmm...
Per usual one step forward and two back. No amount of praying and torquing will make that taper go away and I can't bring myself to assemble a motor that I know for sure needs a hone. I ordered the .50mm OS pistons and with any luck the back order wont be too long,,,then back to the machine shop,,,again. So, it appears as though I will have a VTR1000 for real and not a puny ole 996.
Hey Ace a side question. I have a good motor sitting in my garage. Its pretty simple to just do the .5 bore on the cylinder then put the pistons in right? No other mods needed? If I wanted a bit of a boost with minimal commitment?
I have done it on smaller racebikes but how would the hawk be?
