Member Contributer Mohawk Posted July 24, 2014 Author Member Contributer Share Posted July 24, 2014 I did get the info from Brian, posted in another thread. No rocket science involved. They bored out the MMC & inserted a 2mm steel liner & fitted 76mm JE pistons for a nominal 870cc, more torque everywhere but the HP figures we're let down by lack of other tuning to increase the breathing at speed & the fact that the JE pistons were heavier than stock, so could not benefit from high revs. Link to comment Share on other sites More sharing options...
Member Contributer HighSideNZ Posted July 24, 2014 Member Contributer Share Posted July 24, 2014 I contacted TTS in the UK re the big bore kits that they used to offer and this is what I got backup. Hi, we can still supply the VFR800 bore kit, these are made for us by JE & take the capacity out to 837cc with a comp ratio of 13:1, cost for the pistons £500, the cylinder will need to be bored & re-plated cost for this process £600, plus shipping back to NZ ?? cost for the shipping £100, we have aproxx a 4 week turn round on these kits & plating. regards Paul Paul BembridgeTTS Performance Unit 3 West End FarmSilverstoneNorthamptonshireNN12 8UYENGLAND TEL: +44 (0)1327 858212FAX: +44 (0)1327 858099 www.TTS-Performance.co.ukwww.RotrexSuperchargers.co.uk Was a bit pricey for me as 1200 UK pound is close to $2400 NZD Hence why I'm going with the CBR929 and a local borer. Phil Link to comment Share on other sites More sharing options...
Member Contributer Mohawk Posted July 27, 2014 Author Member Contributer Share Posted July 27, 2014 I spoke to them too. They send the top case to the USA, to be bored & nikasil plated. No way they have a 4 week turn around, be lucky to get it in 4 months ! Link to comment Share on other sites More sharing options...
Member Contributer HighSideNZ Posted August 5, 2014 Member Contributer Share Posted August 5, 2014 The crankcase is currently being bored and I should have it back by the end of the week. Had to supply the machine shop with the crankcase main bearing bolts so as they could fit the case to their jig, These bolts are M9 thread, yep that is right M9 In all my years I've never seen a M9 bolt. I'll update the thread once I've got the cases back. Link to comment Share on other sites More sharing options...
Veefer800Canuck Posted August 5, 2014 Share Posted August 5, 2014 pics when you can? Link to comment Share on other sites More sharing options...
Member Contributer Rush2112 Posted August 5, 2014 Member Contributer Share Posted August 5, 2014 Yes, pics please... and are you having the bore plated with Nikasil? If not, what kind of a finish are they putting on the MMC? Link to comment Share on other sites More sharing options...
Member Contributer HighSideNZ Posted August 6, 2014 Member Contributer Share Posted August 6, 2014 My understanding is that there is no need to plate the MMC as once honed it works just like cast iron liners. Hence why they offer 0.25 and 0.5mm oversize pistons as spares. I'll post pics once ive got all the bits back. Link to comment Share on other sites More sharing options...
Member Contributer Rush2112 Posted August 6, 2014 Member Contributer Share Posted August 6, 2014 My understanding is that there is no need to plate the MMC as once honed it works just like cast iron liners. Hence why they offer 0.25 and 0.5mm oversize pistons as spares. I'll post pics once ive got all the bits back. That is my understanding too... I asked because others had posted about the Nikasil plating. Does the MMC liner need a cross-hatched finish for the rings to seat like a steel bore does? Link to comment Share on other sites More sharing options...
Member Contributer HighSideNZ Posted August 6, 2014 Member Contributer Share Posted August 6, 2014 Yep, the bore needs to be honed to the required size and finish just like a cast iron liner. The standard bores had a good 45 deg cross hatching and were in really good shape. I felt quite bad about boring them out. LOL The only time I think you need to Nikasil plate the bores is if you go the whole hog and bore the complete MMC liner out as what happened with the big big bore kits. Link to comment Share on other sites More sharing options...
Member Contributer Dutchy Posted August 6, 2014 Member Contributer Share Posted August 6, 2014 Looks like we got another Burt Munro here............ Link to comment Share on other sites More sharing options...
Member Contributer JZH Posted August 6, 2014 Member Contributer Share Posted August 6, 2014 Or John Britten? Ciao, Link to comment Share on other sites More sharing options...
Member Contributer HighSideNZ Posted August 6, 2014 Member Contributer Share Posted August 6, 2014 Not in either of those gents league and I'm an Ozzie living in NZ. I've had some experience with V4's in the past building a 880cc Superbike back in the '80's. See below. Link to comment Share on other sites More sharing options...
The Phantom Posted August 7, 2014 Share Posted August 7, 2014 ^ Awesome! Link to comment Share on other sites More sharing options...
Member Contributer Rush2112 Posted August 7, 2014 Member Contributer Share Posted August 7, 2014 You 'Da Man!!!! Nicely done HighSide! Now I know who to call ;) Link to comment Share on other sites More sharing options...
Member Contributer rangemaster Posted August 7, 2014 Member Contributer Share Posted August 7, 2014 GREAT article, thanks so much for posting. I love reading all the stuff that has been done to these bikes. Link to comment Share on other sites More sharing options...
The Phantom Posted August 7, 2014 Share Posted August 7, 2014 BTW Burt Munro is still breaking records! http://www.motorcycle-usa.com/321/18966/Motorcycle-Article/Burt-Munro-Breaks-Record-36-Years-After-Death.aspx Link to comment Share on other sites More sharing options...
Member Contributer HighSideNZ Posted August 7, 2014 Member Contributer Share Posted August 7, 2014 Cool story about Burt. Glad to see he is still in the head lines. Link to comment Share on other sites More sharing options...
Member Contributer HighSideNZ Posted August 7, 2014 Member Contributer Share Posted August 7, 2014 Just been talking to the machine shop that is doing the bore and hone. Bore all completed and no issues but they have just checked with the honing equipment suppliers and it seems that the MMC used by Honda is different to what Porsche/BMW etc. use and that is what the shop thought it would be. There may be a different process to hone the sleeves for our stuff as the liners are not the normal aluminium/silica so they probably cannot use the standard lapping process that removes the aluminium and exposes the silica. Being sintered, it might be a diamond hone. Should know tomorrow what the progress/process is. Link to comment Share on other sites More sharing options...
Member Contributer Mohawk Posted August 7, 2014 Author Member Contributer Share Posted August 7, 2014 Very sweet project, were you the rider or mechanic ? And did it ultimately produce any success ? First I've heard of that bike. Are you boring the MMC to 74mm for the 929 pistons ? Looks like I got beat to it ;) Good man. Link to comment Share on other sites More sharing options...
Member Contributer HighSideNZ Posted August 7, 2014 Member Contributer Share Posted August 7, 2014 No, I'm the mechanic. Ran 2 strokes before this with TZ350's, TZ500's and RG500's. Success was an issue. Ran out of money, no sponsors, and then had a cam gear failure that destroyed one head. That pretty much put paid to it as we couldn't afford to repair it. Yep boring the MMC to 74mm Using the 929 pistons same as you were looking at doing. Link to comment Share on other sites More sharing options...
keef Posted August 8, 2014 Share Posted August 8, 2014 I need to say that this thread is becoming fucking awesome. My Vfr has about 160,000 ks on it, when it goes, hopefully I'll be able to ride your coat tails and go big bore. Link to comment Share on other sites More sharing options...
Member Contributer HighSideNZ Posted August 15, 2014 Member Contributer Share Posted August 15, 2014 Guys I've finished the balancing of my rods and pistons and they are soooo close it doesn't matter. See shots below: I've also included a couple of shots outlining the difference in mass of the original 800 piston and what I've been able to get the 929 ones down to without too much issue. I'm still about 0.5g heavier but that is well within the realms of balance factor on the crank and with forged pistons, can't see they are going to break any time soon, when compared to the cast VFR pistons. One thing I did find interesting was the 929 rods that came with the pistons were majorly different in balance than the VFR stuff. I find this amusing seeing the 929 revs higher than the VFR and was designed as a "sports" bike. These are the piston shots Stock VFR piston Modified 929 piston Bored crankcases I'll keep you posted on progress. Just doing the head gasket mods at present and going to check valve reliefs in the pistons. Cheers Phil Link to comment Share on other sites More sharing options...
Veefer800Canuck Posted August 15, 2014 Share Posted August 15, 2014 Nice! Link to comment Share on other sites More sharing options...
Member Contributer Rush2112 Posted August 15, 2014 Member Contributer Share Posted August 15, 2014 Excellent!!! Where did you take the weight off on the 929 pistons? Link to comment Share on other sites More sharing options...
Member Contributer HighSideNZ Posted August 15, 2014 Member Contributer Share Posted August 15, 2014 Shortened the skirts to the same length as the VFR ones and then took weight out under the crowns, above the gudgeon bosses and the gudgeon webs across to the skirts. I'll see if I can get a photo or two of the pistons and post. Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.