Guys (and girls)..just wondering about personal experiences with the above - I've just got to the stage of dismantling a gsxr 250 with extensive water damage to the bores - very similar to franksters last pics with water ingress albeit on a different engine - will need new pistons which I've got here but struggling on finding a set of useable bores/barrels. I've got several around in various states but all will need boring by at least 1-1.5mm as a minimum to make them useable - and yes no o/s pistons available after 0.5mm o/s now either. More than anything I'm looking for standard reliability - my questions are thus; Plating - essentially building up the bore and re machining back to standard size - does it last? Sleeving/Lining - Boring out the cylinders to accept new sleeves (but have heard it sometimes leads to the sleeves moving - can only imagine if it happened the results at 15k rpm will be catastrophic) Apticote - the best of what I've heard similar to plating Ideas? Thoughts will be noted and more likely used if they provide a solution!!! Cheers Si
Funny you should mention that. I am painting my Yamaha engine at the moment. The sleeves are an interference fit and can easily be removed by heating the block. I imagine the Suzuki will be the same.
Is the Yamaha semi wet liner? Reason I ask is that the barrels are definitely an interference fit..but not totally sure how to relocate them if that's the right word after removal/replacement/reconditioning..in the dark on this one as not done it before..local machine shop says the swap will be 480£..not sure what that is in AUS$ but its a lot of coin on top of the barrels being renovated (200£)..a new block is the same price but sadly no longer available..oven, ice to remove, oven and mechanics(flat bench) to replace? Will it last as long as OEM stuff and can it be done at home..any help greatly appreciated, thanks blair, si
It looks like a wet liner but the aluminium actually runs all the way up to the lip, so it is a simple lipped sleeve. They have a flat on the edge of the lip where the two lips would otherwise touch so can only be fitted in the same position. Would require new sleeves turned from blanks then fit. As good as OEM? Sure if you can find some good quality sleeve material. I used to use Jawa speedway bike sleeves in oversize Ducati engines, outstanding material. Be wary of a well known US brand. I think in the UK it should be easy to source good blanks and then some accurate turning to exactly match the standard OD of the sleeves you removed. It costs more to bore blank sleeves because they have to take more cuts. Fit one at a time. As you said cool sleeves hot block. They just drop in but the aluminium contracts too quickly to do more than one at a time. If it grabs don't start hitting it. Just put it all back in the oven and you will get it home with some light taps.
Here you go That wet looking substance is some horrible wax that only melts at high temp. I think it could be "seal your radiator leak in a bottle" garbage. In any case it will act as an insulator so I am trying to get rid of it.
Genius..my questions answered matey ..simple lipped sleeve - I was in two minds as to if it was wet - on closer inspection its precisely - a simple lipped sleeve!!!I will go and prep up one of the blocks I've got and see if the misses will let me use the oven - better still she's off out shortly lol - I'm thinking it might be cheaper to get a small run made of 12 or 16 liners/sleeves than going down the route of 4 and then needing more later in times to come as I can only see the parts situation getting worse over time..ideas on the material? Sorry for being cheeky but from your post above you've obviously got experience to fall back on..I'd rather listen to the knowledge than make a mistake i'll regret later!!! Cast iron, ductile iron? I'm pretty limited in my knowledge of the way the ring material will interact with the bore..the company I'm intending to use is http://www.laystall.co.uk/cyl-high-performance.php, from what I've read their reputed to be at the top of their game..but offer a whole host of different materials..should I just take their advice on what they think is best - or specify the best material to use? Better to send them a new set of pistons and rings and a whole damaged (sleeves only) block so they can get the tolerances spot on..or just the sleeves specifying the OEM internal bore diameter - it will be miles cheaper..ideas appreciated buddy. One question remains, will they be able to replicate the cut outs at the top of the sleeve for the valves on the intake side and also the angled base of the sleeve which assists getting the block back on over the pistons come rebuild time without the need for ring compressors..always a tricky job due to the clearances involved..really appreciate your comments boss, cheers si
Only the OD is finished to size. The ID is left undersize then bored and honed once the sleeves are fitted. Cast Iron is the weapon of choice. Those reliefs for the valve can be done by hand with a die grinder. Get the old sleeves out and number them. Then measure with micrometer, not vernier calipers, and send drawing to company. Or just send the 4 sleeves to the company. Then once you fit the new ones you are ready to have them bored and honed to your new pistons. In fact I would do those valve reliefs with a file. Edit: And make the lips 0.5mm thicker so you can deck the block once the sleeves are installed. Edit 2: 150 to 180 C should be more than enough for the aluminium to expand to its maximum. If the sleeves are a little reluctant to drop out I would have a local machine shop turn up a steel disc that has an OD slightly less than that of the sleeves and a section of the length to a diameter slightly less than the ID of your bore. Then you can sit that into the bottom of the sleeve and tap them out.
Yep, that is just what you want, centrifugally cast iron. But I would go with the cylinder sleeve shop unless you want to do some more research, From Wiki: Typical parts made by this process are pipes, flywheels, cylinder liners and other parts that are axi-symmetric. It is notably used to cast cylinder liners and sleeve valves for piston engines, parts which could not be reliably manufactured otherwise.
@anyone who's interested... regarding materials for cylinder liners: Assuming that you are going to be running on the iron, and not going to use a hard coating (nikosil etc. which can be added to iron, just as it can be to aluminium) then it's not as simple as any cast iron if you want to get something like manufacturers service life. Remember, Burt Monroe never put on the amount of miles you'll want to be doing, never worried about oil consumption like you will, and was probably running piston clearances that you could fall into. What is ideal is a grey cast iron - not a ductile iron, and a grey cast iron with a predominantly pearlitic structure. Obviously the first port of call is your engine machine shop as maelstrom suggests as they'll know this, but if you're thinking of going to a machine shop with a sketch of a liner and a lump of material you've sourced yourself then a piece of drain pipe or a cast iron cooking pot won't do the job irrespective of it being centrifugally cast or not. You've got to have that pearlite. I would suggest a cylinder off a two stage piston compressor (the higher pressure stage will have to be iron due to the pressure, and will be a smaller diameter) or even an old lawnmower barrel would be a better starting point, even if it means extra cost due to there being a lot of fins to machine off. If you have got a local foundry that will cast small batches (you'll need a least 4 of course, after you've thrown half away due to porosity) then ask for grade 250 grey cast iron, but with the addition of a little copper or chrome to get that pearltic matrix. This will probably result in a tensile of 275, but that's not the important bit, it's the matrix. If they look at you like you're from mars then go elsewhere. Once they're machined, installed and finish bored, then you've got to get them honed, but that's a subject for another day, and from looking at how every honing and running in post on other forums descends into a ruck, it makes me think it's one we should avoid!
As Simon has mentioned, there are already specialist firms like that produce cylinder sleeves. Murdo and I go off on tangents at times.
Praise be 'Edit 2' wasn't needed..gas mark 5 for half an hour..gives about 60-90secs of working time!! Relief!! An update guys...I've got the specs measured, sleeves are out..will send them off over the weekend - I'm leaving the final work to the sleeve manufacturer as they've asked for some old rings of similar type for what they term 'matching purposes'..will repost with what material they use on the sleeves - interestingly they've said go 0.25 thicker on the lip to deck the block and are also going along the lines of centrifugally cast iron - Blair common sense/experience, I know but missed it boss So I'm feeling a bit more at ease as it concurs with all of the advice above..they might, just might know what there doing! I'll let you know how I get on after the rebuilds underway, pics to follow..to all - this is not an inexpensive job - the cost is pretty much at 70pc of a new block - any thoughts on the best piston/cylinder clearance once done - or factory specs? Thanks to all, the advice is greatly appreciated, Cheers si Ps abel I haven't yet asked about the 250 grade grey cast iron but will endeavour to do so prior to giving the green light..thanks for the input buddy
That all sounds perfect Simon. Judging by the information on their web site they are a good company and know what they are doing. Go with factory spec for clearance. The next trick will be finding someone to bore and hone the cylinders correctly. I wrote a thread about fitting new rings http://2fiftycc.com/index.php?threads/hone-fit-new-rings.2939/ and about halfway down is a link to a Millenium Technologies video. You want it done to that standard. You will hear lots of people recommend "such and such are really good". Now sure they mean well, but the road to hell is paved with good intentions. Those well meaning people usually use a Chinese digital vernier caliper as their precision measuring instrument, so not a good idea to be advising others on the accuracy of a precision machining job.
@Simon, if you don't mind, how much was it for just the blank sleeves and how much to machine the OD and lip. That information would be useful for everyone. PS: The sleeves are not very tight, if they are anything like my Yamaha, so you will need to take fine cuts with the boring bar and/or use a torque plate.
