Member Contributer Rush2112 Posted June 16, 2015 Member Contributer Share Posted June 16, 2015 Woo-Hoo! Nice work, Sir! HP still climbing at 12k rpm... I'd say she's breathing better! I know you mentioned the pipes and cams but sell don't yourself short and discount the HRC spec port & polished heads! I'm curious to see the mid-range and torque curve. Well done! Link to comment Share on other sites More sharing options...
Member Contributer HighSideNZ Posted June 17, 2015 Member Contributer Share Posted June 17, 2015 OK Got the graph from the dyno last night and have applied the corrections to bring it to DJ type figures. EG: +12% The sweep we did I ended at about 11500 RPM due to the coolant leak but the graph clearly shows it still pulling strongly at that RPM. The maximum torque at that RPM is in the order of 66 ft/lb so a good increase over standard. As you can see it is pretty linear and the torque really come on strong from about 7500 RPM. The red lines on the grpah are the corrections that I've put in place at +12% Graph attached. Cheers Phil Dyno Graph Corrected to DJ.pdf Link to comment Share on other sites More sharing options...
Member Contributer mello dude Posted June 17, 2015 Member Contributer Share Posted June 17, 2015 Suh - weet!!!! Link to comment Share on other sites More sharing options...
Member Contributer Rush2112 Posted June 18, 2015 Member Contributer Share Posted June 18, 2015 Nice!!! :cheerleader: I shall toast your success immediately! Link to comment Share on other sites More sharing options...
Member Contributer Mohawk Posted June 19, 2015 Author Member Contributer Share Posted June 19, 2015 Just did some extrapolation on this myself & IIRC then the modified 929 pistons are the same weight as the OE ones, so your engine should with a good waterpump be able to rev to the STD engine limiter at 12,200rpm. If you wanted at extra 300rpm, then Dimsport can do that remotely for you ! Looking at the graph that extra 1000rpm would easily put that at over 140djhp amend if the torque stays the same or keeps climbing, then you'd be looking at 150-155 for 12,200-12,500rpm. So your exhaust is working pretty well :) Fantastic job. Link to comment Share on other sites More sharing options...
Member Contributer Mohawk Posted June 19, 2015 Author Member Contributer Share Posted June 19, 2015 Hi CandyRed, thanks for the info, but the guys in lala land. The MMC is made from the same grade alloy as the upper crankcase, so immersing it in acid, would erode the whole crankcase ! So no thanks to that one. I have it on good authority from an RC45 tuner that the MMC can be bored like any iron liner, but needs a diamond hone like Nikasil. Regarding the cc to bang ratio, the whole is worth more than the sum of its parts. VFR750 4th gens make an average 90rwhp, but bored to 837cc (+87cc) they put out 133rwhp (+43hp or 47%) . If we look at the percentage ratios for this, it's a 11.6% cc increase, so 750/90=8.33cc per hp, so 87/8.33=10.4 extra HP, but the 837cc makes 47% more power ! This is achieved with NO other tuning ! So taking the 800 (actual is 782cc) to 74mm bore = 825cc is +43cc (5.5%), or to 75mm bore = 848cc is +66cc (8.44%). So if we assume that similar gains to the 750 would be seen on a bigger 800, then using the same 47% power increase for the 750 & extrapolating it to the 800 with a base 95hp, would be as follows;- 750+87cc=837cc=+47% hp =133rwhp 782+43cc=825cc (87/43)= +23% hp = 117hp 782+66cc=848cc (87/66)= +35% hp = 128hp Or based on my existing tune of 107rwhp & using the same percentages above, then I'd expect to see 825cc=130hp or 848cc=140hp. Now that would be impressive :) I have a few tweeks planned for the existing tune to bring it up towards 120hp. If I could pull that off then those tuned figures should certainly be attainable. All hypothetical until I actually cut metal, roll on the winter :) Just reviewing my very early calcs now that the real metal results are in, so 95hp on STD bore goes to 135hp on 825cc with some mild cams & a freer breathing exhaust ! Good empirical data to back up the thoery :) To man Phil. Link to comment Share on other sites More sharing options...
Member Contributer HighSideNZ Posted June 19, 2015 Member Contributer Share Posted June 19, 2015 Hi Mohawk The 929 pistons are a few grams heavier than stock but by the time you deck them etc. I ended up with the full piston/pin/ring assembly being exactly the same as stock so balance factor stays as it should. By the time you balance the rods to within 0.5 g and the pistons the same, the engine revs nicely and it would I feel rev well to the 12.2k plus 500 rpm. I have the full RB software with the USB key so I can alter the limit myself but currently I quite happy with the result and torque as it is. I feel there are a few hidden ft/lb in the mid range in ignition timing and I'm going after those at present, together with getting the single nut rear wheel conversion underway. I'm also looking hard at the Yoshi 2 stage intake trumpets. Just need to work out what I'm going to use seeing I've already ported the throttle bodies to match to the R6 trumpets I'm currently using. Link to comment Share on other sites More sharing options...
Member Contributer Switchblade Posted July 9, 2015 Member Contributer Share Posted July 9, 2015 Have you got to put her through the paces and whats it like . Link to comment Share on other sites More sharing options...
Member Contributer HighSideNZ Posted July 9, 2015 Member Contributer Share Posted July 9, 2015 Weather has been pretty shite here lately. Mid winter, so not much riding. It looks like it is going to be fine but cold this coming weekend so hope to get a few kms in. Will let you know how I get on. Link to comment Share on other sites More sharing options...
Member Contributer Switchblade Posted July 9, 2015 Member Contributer Share Posted July 9, 2015 Thanks . Link to comment Share on other sites More sharing options...
Member Contributer Switchblade Posted July 9, 2015 Member Contributer Share Posted July 9, 2015 Add some video and they will probably rename the forum to "HighSide VFRD". Link to comment Share on other sites More sharing options...
Member Contributer Mohawk Posted July 26, 2015 Author Member Contributer Share Posted July 26, 2015 Hi Phil, Been a few weeks, hows the bike going ? Link to comment Share on other sites More sharing options...
Member Contributer HighSideNZ Posted July 27, 2015 Member Contributer Share Posted July 27, 2015 Hi Chris The weather has been fairly crap here so it has given me a chance to get the single nut conversion rear wheel well underway. The bike has been going really well when I've had a chance to ride. Should have the rear wheel conversion completed next weekend. Just waiting on a couple of new 38mm axle nuts to arrive from the UK at present. Got everything in place yesterday and it has shaved about 3.2kg off the unsprung weight on the rear. Just need to button it all up once the nut arrive. At that stage I'll create a new post and upload the drawings I've made of all the mods. Cheers Phil Link to comment Share on other sites More sharing options...
Tarrant Posted July 28, 2015 Share Posted July 28, 2015 Holy crap... I'm envious of your time and skills. Link to comment Share on other sites More sharing options...
Member Contributer Mohawk Posted July 28, 2015 Author Member Contributer Share Posted July 28, 2015 Phil's my apprentice :). Just kidding ! Good news, matches with my figures, mine saved 6.2Kg but that included 3Kg from the wheel ! Link to comment Share on other sites More sharing options...
Member Contributer HighSideNZ Posted July 28, 2015 Member Contributer Share Posted July 28, 2015 Yes it seems to be the Mohawk and HighSideNZ show LOL Chris comes up with the ideas and the prototype, then I have a go! Must be my time to lead. Going back over my figures I reckon on 3.0-3.1kg with my steel bits. Was a little optimistic with my maths. Got to be a good overall effect on the rear suspension, and with the reduction on the front end with the R1 gear and no linking, not sure if I could get it much lighter without a metric butt load of $$. Link to comment Share on other sites More sharing options...
Veefer800Canuck Posted July 28, 2015 Share Posted July 28, 2015 Less talking, more rear wheel pictures......... Link to comment Share on other sites More sharing options...
CandyRedRC46 Posted August 18, 2015 Share Posted August 18, 2015 Pics please :) Link to comment Share on other sites More sharing options...
Member Contributer HighSideNZ Posted August 18, 2015 Member Contributer Share Posted August 18, 2015 Hi CRRC46 There is a completely separate thread for this mod, with pic's and drawings. http://www.vfrdiscussion.com/forum/index.php/topic/81706-single-nut-rear-axle-conversion-6th-gen/ Cheers Phil Link to comment Share on other sites More sharing options...
RVFR Posted March 8, 2016 Share Posted March 8, 2016 Wow, what a read, what an adventure, way to stay the coarse, I'll need to preserve this thread for future referencing.. Nice job, talk about dedication. Those numbers aren't to bad either ;) Hey! Honda, you see this? Link to comment Share on other sites More sharing options...
Veefer46 Posted March 29, 2016 Share Posted March 29, 2016 Hey Phil, it's been a while but I'm glad you were able to complete the project with results that good! After starting with my first job and moving out last year I finally found the time and a few bucks to carry on with the project. Well - at least the engine is bored and honed I bought the SC44 pistons already last year and inspected the engine more thoroughly for wear. Basically I need new gaskets, bearings (especially main-bearings) and piston-rings. But those Honda-parts are somewhat expensive! Did you buy new piston-rings for the used SC44 pistons? Actually they're looking quite good and the gap should also be in spec from what I saw when I put it in the slug (need to remeasure properly). I'd just like to know if it's really necessary to spend 95€ (nearly 160 NZD) for the rings of just one piston. I couldn't come up with aftermarket ones either. I will ask local dealers here but normally they are even more expensive than the ones online. Any input on this would be appreciated, perhaps someone knows good sources for Honda spare parts in general Kind regards, Julian Link to comment Share on other sites More sharing options...
Member Contributer HighSideNZ Posted March 30, 2016 Member Contributer Share Posted March 30, 2016 Hi Julian I did rings, pins, bearings the whole shooting match when I did mine. I didn't think the rings were that bad, cost wise. I bought all my spares from Partzilla in the US and at that stage the NZ$ was very high against the US$. Would be a different situation now as 1 NZ$ buys about 0.64 US$ My thinking was do it once, do it right. 13031-MCJ-000 RING SET (STD) (American Honda) $28.86 Shipped Monday, August 04, 2014 4 $115.44 That is what I paid in 2014 for the ring sets for ALL 4 pistons $115.44 Cheers Phil Link to comment Share on other sites More sharing options...
Veefer46 Posted June 12, 2016 Share Posted June 12, 2016 Hey Phil, thanks for the tip. In this case I will do it all new - gives a better feeling :) I am in the process of calculating how much I have to remove from the piston deck in order to get some reasonable static CR. This is what I measured: Volume head chamber: 14,200mm³ (one was 14,100mm³, the rest was pretty similar) Volume gasket (my old one measured 0.65mm thickness): ~2800mm³ Volume crankcase at 2mm below TDC: std. piston in 74mm bore: 9800mm³ --> should be 9340mm³ in the 72mm bore --> Volume crankcase at TDC: std. piston in 72mm bore: 1200mm³ 929 piston in 74mm bore: -1400mm³ These numbers get me a 11.74 static CR for the original build (which is pretty close to Hondas calculation) and 14.24 for the unmodified 929 piston. Quote Hi GLL429 Yep you are probably right. There are lots of bikes out there with massively overbored blocks without issue. It's just that In cannot make the standard advertised Honda figures add up and this has me really perplexed. Phil Removing 1mm overall from the 929 piston via lathe would give me a static CR of 12.15 which I thought I was aiming for. You kept the dome 1mm above the squish area like the VFR, though. According to my CAD-calculation this would give me a CR of around 13.3. Is this what you went along with? In this case I cannot really figure out what your drawing is about Thanks, Julian 929 piston mods.pdf Link to comment Share on other sites More sharing options...
Member Contributer Mohawk Posted June 12, 2016 Author Member Contributer Share Posted June 12, 2016 Beefier, static CR is pointless, just calculate the dynamic CR, std VFR is 10.96/1 IIRC. With my longer duration cams mine is around 10.3/1. Link to comment Share on other sites More sharing options...
Veefer46 Posted June 14, 2016 Share Posted June 14, 2016 Hi Mohawk, due to the fact that I keep my standard cams in first place I am caluculating static CR. I'd just like to compare the values respectively ask what you think could be possible with 95 Octane (98 would be possible as well). Thanks, Julian Link to comment Share on other sites More sharing options...
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