Member Contributer Dutchy Posted December 11, 2013 Member Contributer Share Posted December 11, 2013 hahaha!!! Douglasthecook is on it like a fly on a marmelade jar!!! I know he wants a big bore!!! Link to comment Share on other sites More sharing options...
Member Contributer Mohawk Posted December 11, 2013 Author Member Contributer Share Posted December 11, 2013 Did TTS say who they send the block to in the U.S.? Unfortunately no & I didn't ask. You could always call or email them to find out. Link to comment Share on other sites More sharing options...
douglasthecook Posted December 12, 2013 Share Posted December 12, 2013 Do you happen to have an e-mail for TTS? Where I am currently at, I do not have phone aervice, and am lucky to have internet access, so e-mail will be the best way for me to contact them. Link to comment Share on other sites More sharing options...
Member Contributer Mohawk Posted December 12, 2013 Author Member Contributer Share Posted December 12, 2013 No email, but they have an online contact form here http://www.tts-performance.co.uk/#!contactus/c19rm Link to comment Share on other sites More sharing options...
douglasthecook Posted December 12, 2013 Share Posted December 12, 2013 Excellent, that'll work, thanks!!! Link to comment Share on other sites More sharing options...
Member Contributer Ultimatevfr Posted December 12, 2013 Member Contributer Share Posted December 12, 2013 God I love this place ! ;) Link to comment Share on other sites More sharing options...
Member Contributer Mohawk Posted December 12, 2013 Author Member Contributer Share Posted December 12, 2013 Ladies & gentlemen, I give you one x Honda VFR800 MMC liner for your deliberation :)Having made a second cut to find the horizonal locking tabs, it appears Honda did away with that design as it was probably difficult to manufacture & replaced it with a far simpler system that turned some horizontal grooves into the MMC & let the casting lock into those.This is good news for you Big Bore fans, as it means the liner is thiner than previously expected :)This liner I removed is between 2.41-2.55mm thick at its thinest section & 2.69-2.91mm at its thickest, these measurements were taken at 6 points around the circumference for both thin & thick points.It is evident that the casting process does NOT produce the finished bore allignment & that the liners are bored or honed insitu as part of the upper case machining process.So if we say a nominal 72mm bore & a nominal 8mm combined MMC & casting liner thickness, giving a measured 88mm outer diameter on 8 cylinders from 2 blocks, then;-1. A 6mm overbore is required to totally remove the MMC liner, giving a nominal 78mm bore.2. A 78mm bore would leave only 5mm wall thickness, this may NOT be sufficient even if Nikasil plated.3. There is what appears to be evidence of water ingress between the liner & the casting, a thinner liner my increase this effect due to capillary action & increased flexation.4. A thinner MMC liner may flex more & may crack of D chunk off causing engine damage, this is common in some newer Porches.5. The last big bores for these engines were 76mm, TTS did Nikasil, which means they were running the liner at .5mm thick or slightly less allowing for a .1mm nikasil thickness !6. A 78mm bore would yeild a 916cc VFR !!!!!!7. Wiseco do a 78mm piston for the CBR1000RR with the correct 17mm wrist pin diameter !Would this work I don't know (yet), more research required. But food for thought :) A quick calculation based on HP per CC says that my state of tune engine with a 916 displacement would deliver 125rwhp ! Link to comment Share on other sites More sharing options...
Member Contributer Mohawk Posted December 12, 2013 Author Member Contributer Share Posted December 12, 2013 Before anyone says it, no I have not looked at compression ratios for that huge bore increase ! Link to comment Share on other sites More sharing options...
Member Contributer spinalator Posted December 13, 2013 Member Contributer Share Posted December 13, 2013 Good work! Link to comment Share on other sites More sharing options...
Member Contributer JZH Posted December 14, 2013 Member Contributer Share Posted December 14, 2013 TTS probably won't tell you their supplier...but it should be pretty easy to figure it out. I think there's only one "known" shop for that kind of work...but the name escapes me at the moment! Aaaaarrrggghhh. Their name comes up all the time for this kind of mod. It's probably mentioned in this thread! 916 has a nice ring to it...hmm... Ciao, Link to comment Share on other sites More sharing options...
Member Contributer mello dude Posted December 15, 2013 Member Contributer Share Posted December 15, 2013 TTS probably won't tell you their supplier...but it should be pretty easy to figure it out. I think there's only one "known" shop for that kind of work...but the name escapes me at the moment! Aaaaarrrggghhh. Their name comes up all the time for this kind of mod. It's probably mentioned in this thread! -- Is it Millennium Technologies? http://www.mt-llc.com/cylservice.php Link to comment Share on other sites More sharing options...
Member Contributer CornerCarver Posted December 16, 2013 Member Contributer Share Posted December 16, 2013 I can no longer get the "quote" button to work...Mohawk, I understand that you have not looked at compression ratio with the larger bore, have you confirmed that the wrist pin height is the same with the CBR pistons? The shop that TTS sends their boring out to is indeed Millennium Technologies in Wisconsin... From Paul at TTS...They offer 74mm kits for both the 750 (837 after kit) and the 800 (839 after kit) 750 has iron liners and just requires a standard bore and hone. The 800 needs to be bored and Nikasil plated, we use Millennium Technologies in Wisconsin and you can deal directly with them. The pistons and custom made for TTS by JE in Californina, so these need to be ordered through TTS, cost for pistons including shipping is 500 pounds... Link to comment Share on other sites More sharing options...
CandyRedRC46 Posted December 17, 2013 Share Posted December 17, 2013 i need an vfr848 bad Link to comment Share on other sites More sharing options...
Member Contributer Mohawk Posted December 17, 2013 Author Member Contributer Share Posted December 17, 2013 Unfortunately the 848 can't be done, unless you can get the un sleeved bore re sleeved or welded up & plated. 74mm is as large as II'd dare with the current MMC liner. Regarding pistons, the CBR929/954 74/75mm pistons have the same sized valves. The exhaust valves are the correct spacing, the inlets are slightly further apart, so would need a little ground out of the valve separator on the piston crown. The deck height around the piston rim would require some material removed to match the head profile. The crowns are close & may be useable as is, depends on how much clearance is in the head already. Unfortunately only a dry build will reveal the answer. I intend to send my sacrificial top crankcase to TTS for normal boring testing, with a 929 piston for them to match & see what happens next ! More news when I have some. The 78mm Wiseco option is probably NOT. A real option. I calculated the compression ratio & it's 12.5/1 which is OK, but I also got the weight of the bare piston & it's 249grams bare, where as the 800's standard piston is 238 compleat with rings & wrist pin. The wrist pin is 50 grams, so a complete 78mm piston would weigh about 310-320 grams, which is way to heavy for the existing rods ! CBR1000RR 76mm pistons might be useable, as the 954 complete is 225grams & the 76mm should be similar to the VFR's but would require a major machining job. Link to comment Share on other sites More sharing options...
Veefer800Canuck Posted December 17, 2013 Share Posted December 17, 2013 So a 74mm bore gets 826cc's yes? So not quite 6% increase. All else being equal, that comes to about 112 Hp with no other modifications besides the bore job. (guess) Cost/benefit seems to be kinda low. I'm still interested to watch, and see what the results are. Link to comment Share on other sites More sharing options...
Member Contributer CornerCarver Posted December 17, 2013 Member Contributer Share Posted December 17, 2013 According to TTS 74mm yields 837 in a 750 and 839 in an 800...still probably close to your 110-115hp estimate. I will continue to pursue a complete re-sleeve of the 800 that nets above 900cc - the closer to a V4 liter bike the better. Link to comment Share on other sites More sharing options...
Member Contributer Mohawk Posted December 17, 2013 Author Member Contributer Share Posted December 17, 2013 According to TTS 74mm yields 837 in a 750 and 839 in an 800...still probably close to your 110-115hp estimate. I will continue to pursue a complete re-sleeve of the 800 that nets above 900cc - the closer to a V4 liter bike the better. Well I'd love to know how they calculate 839cc, I bet they cocked up & did the calc with the 750's stroke which is longer ! It's definately 825-826cc for the 800. Well 78mm will get you 916cc & would require a lot of work. Be nice to see someone do this, but again would require new rods, rebalanced crank, new sleeves, cylinder reinforcing etc, plus possibly some extra cooling ! Link to comment Share on other sites More sharing options...
Member Contributer YoshiHNS Posted December 17, 2013 Member Contributer Share Posted December 17, 2013 According to TTS 74mm yields 837 in a 750 and 839 in an 800...still probably close to your 110-115hp estimate. I will continue to pursue a complete re-sleeve of the 800 that nets above 900cc - the closer to a V4 liter bike the better. If you come across any information on how thin you can leave the wall before you fit the other sleeve that would be great. I was thinking I could do some calculations just based on the forces from the shrink fit, but I have nothing to go on to estimate the forces perpendicular to the stroke. Link to comment Share on other sites More sharing options...
Member Contributer Ultimatevfr Posted December 18, 2013 Member Contributer Share Posted December 18, 2013 Don't shoot the new guy , ....but I take it that the 1100 block is drastically different then the 800 block ? Link to comment Share on other sites More sharing options...
Member Contributer Mohawk Posted December 18, 2013 Author Member Contributer Share Posted December 18, 2013 The standard wall inc MMC is 8mm thick. Minus the MMC it's 5mm thick. 870cc was achieved with 76mm bore & 2mm steel liner, so giving a minimum wall thickness of 4mm. You could reinforce the wall & go to 80mm with nikasil bore. That would give you 964cc if you could find a piston to suit & do all the other work required. For the find of money involved a custom Rotrex super charger kit woul be cheaper ! Link to comment Share on other sites More sharing options...
Member Contributer YoshiHNS Posted December 19, 2013 Member Contributer Share Posted December 19, 2013 How do you define 'reinforce the wall'? Link to comment Share on other sites More sharing options...
Member Contributer Mohawk Posted December 19, 2013 Author Member Contributer Share Posted December 19, 2013 Well the wall is 8mm thick as standard, I've measured this on two engine, so 8 cylinders. The block is what they call open deck, so the cylinders stand proud on there own & seal to the head gasket. On IL4's there is NO inter cylinder cooling. On the VFR800 there is 5mm of inter cylinder cooling gap. So your options are;- 1, Ring reinforcement, where a separate steel/SS or 7075 alloy ring 1-2.5mm thick & 15-30mm deep is heated & slipped over the outside of the cylinders thus reinforcing them. 2, Do what the Big Bore car guys do & fill the lower half of the water void with a solid setting filler. 3, Ad an open deck reinforcing baffle (search for blox block guard) to reinforce complete cylinder top. These sort of make the block closed deck. It does the same as 1, but connects everything together & uses the water jacket as part of the reinforcement. They use these on big bore or blown honda car engines. Hope that helps. Link to comment Share on other sites More sharing options...
Member Contributer JZH Posted December 20, 2013 Member Contributer Share Posted December 20, 2013 IMHO, a 10% power increase is not worth the considerable expense. FYI, I have TTS-built VFR837FP and VFR444RN, and I did them because I could, not because I can really tell much of a performance difference. Comparing back-to-back with similarly tuned regular displacement versions would probably make it noticeable, but I've never had a chance to do that. Yes, I was referring to Millennium Technologies, as (surprisingly) confirmed by TTS. I also know that Mike Norman of G-Force Engine Development in California has done a lot of work developing NC30 racing engines, but I don't know if any of his knowledge would transfer over to the bigger VFR engines. Ciao, Link to comment Share on other sites More sharing options...
CandyRedRC46 Posted December 20, 2013 Share Posted December 20, 2013 Yeah I don't see this helping with peak hp too much with out supporting breathing mods (torque should increase greatly, as well as hp under the curve, midrange and low end, but with tiny headers and throttle bodies/velocity stacks, there is only so much air that you can get through that engine, regardless of displacement.). But with larger throttle bodies, headers, a good port and polish on the heads and 1mm or 2mm larger valves to take advantage of the larger bore; now you're talking real power. Link to comment Share on other sites More sharing options...
Dannytb Posted December 21, 2013 Share Posted December 21, 2013 Yeah I don't see this helping with peak hp too much with out supporting breathing mods (torque should increase greatly, as well as hp under the curve, midrange and low end, but with tiny headers and throttle bodies/velocity stacks, there is only so much air that you can get through that engine, regardless of displacement.). But with larger throttle bodies, headers, a good port and polish on the heads and 1mm or 2mm larger valves to take advantage of the larger bore; now you're talking real power. Just thinking... That amount of work to make it breathe better, and leaving the bottom end alone would probably be better bang for buck, without the potential durability issues of the overbore. Add in a custom cam grind to RC45 spec, and the expense of over-boring doesn't make so much sense. Hmmm... How to increase the spark advance to unlock a few more ponies??? ;) All of that being said, it would be pretty cool to be able to say "I have a VFR900" or "I have a VFR1000"... To this end, if someone's going to the expense of doing a 76mm bore, they might as well at least look into stroking it up a bit more while they have the engine apart! Link to comment Share on other sites More sharing options...
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