tomek Posted March 4, 2007 Share Posted March 4, 2007 Well,I pulled out cylinder head from my 99 XX.It was fairly easy job,had to make one special tool ( 3/4 inch socket had to die). I left rear lower bolt and ,well,lowered the motor. Here is what I`ve found out. Top of cylinder head in excellent shape,cams,bearings,buckets,springs in excellent, almost new shape.That is a good news. Bad news,valve seats and valve`s sealing surface in poor shape.There is no question it was a leaky motor.Valves never needed adjustement,but I alwayes tried to get more or less same clearance on all of them,motors runs better this way.I mean, spec lash is 0.13-0.19 for intakes but if you get them within 0.01 motor will run better. I`ve had no plans for new valves and recut seats so just good lapping had to do .Now I have wide sealing sufrace( still within spec). Cam timing.Intake was 108.5 ( spec is 101.5) exhaust 97.5 ( 100spec).Normally when cam chain and the guide wear out cams do get retarded,that explaines exhaust,it is 2.5 deg retarded, but intake is 7 deg out,dude who drilled holes in intake sprocket had too much sake day before,no question about that. It also explaines why my motor was gutless in midrange,but pulled all the way to the rev limiter without power drop. I believe sport bikes should have adj. cam sprockets stock and adjustment should be done during valve checks. Ports. Intake ports are fucking huge,they represent 80`s and early 90`s thinking,bigger was better.Intake port velecity at 10000 rpm is about 260 ft/sec,modern liter bikes work aroud 330-360 ft/sec.Basically ports are smaller now,Honda`s own 1000rr has 3 mm smaller valves and ports,pulls around 340 ft/sec at 12000 rpm.Yet that bike makes about 20 more hp at the wheel. 1000rr has power everywhere in rev range.Anyway,I`ve redone ports a la` motoman with 30% height reduction,will see how it works.Plus I`ve cut intake guides. Exhaust ports are actually not bad,nice D shape,they got polished. Combustion chambers. Not whole can be done,valves can`t be unshroud becouse valves seats are very close to the edge.Nothing to do here,I`ve polished chambers. Anyone serious should get sunken seats and go from there. Squish.I got 44-45 thou I think,that is after I`ve removed 1 leaf from gasket( worth 0.25mm,O.E.M gasket is 0.75 mm).So stock squish is about 1.35 mm,that is huge,race motors run about half of that.I don`t expect O.E.M. motor to have 0.65 mm squish but 1.35mm . FYI stock 04 R1 motor runs about 0.80 to 0.85mm stock. Basically cylinder block needs to be cut in order to get good squish.With integrated upper crankcase it is just too much work. Cylinder bores look good,no wear marks,I`ve got no clue about pistons and rings. BTW there was very minimal carbon build up in the chambers,intake valves were really clean,none of that crap that blocks airflow. I guess it does pay to use quality detergent gasoline.None of Costco or quick mart,etc crap here. Cylinder head was cut 0.5mm,that plus 0.25mm removed from gasket will bring CR to about 12.1-12.2,( if stock CR is really 11.0).Cams will be set to ex.100 intake 103-104,hopefully it will be much better street motor now.If no improvement,I`ve had fun doing this plus killed dead winter time.Win-win situation. O,yea,I`m also painting my XX (again) and fitting bags form ST Ducati. Quote Link to comment Share on other sites More sharing options...
rockmeupto125 Posted March 4, 2007 Share Posted March 4, 2007 Did you do a dyno pull before you tore it apart? Quote Link to comment Share on other sites More sharing options...
redxxrdr Posted March 4, 2007 Share Posted March 4, 2007 I would love to see pictures of the tear down. With only 29K on my bike, I should have years, and years before I get there. But I will save a link just the same. Since Honda doesn't make anything close to my desires, I will continue to cherish and enjoy my bird. Quote Link to comment Share on other sites More sharing options...
Northman Posted March 5, 2007 Share Posted March 5, 2007 Cylinder head was cut 0.5mm,that plus 0.25mm removed from gasket will bring CR to about 12.1-12.2,( if stock CR is really 11.0). My stock CR measured at 10.7 Quote Link to comment Share on other sites More sharing options...
Pete in PA Posted March 5, 2007 Share Posted March 5, 2007 Now you've got me paranoid. I'm at 76K miles is my top end on its way out? What caused the erosion? Got any pics of the valves and seats? Quote Link to comment Share on other sites More sharing options...
tomek Posted March 6, 2007 Author Share Posted March 6, 2007 Did you do a dyno pull before you tore it apart? Who? Me paying for dyno,are you crazy, my butt duno is the best. O.K. many.many moons ago pulled 143 on really humid day,, I would love to see pictures of the tear down. With only 29K on my bike, I should have years, and years before I get there. But I will save a link just the same. Since Honda doesn't make anything close to my desires, I will continue to cherish and enjoy my bird. Good news,I did take pics of valves and seats,bad news they are out of focus,forgot to put the thing in Macro mode Cylinder head was cut 0.5mm,that plus 0.25mm removed from gasket will bring CR to about 12.1-12.2,( if stock CR is really 11.0). My stock CR measured at 10.7 Avarage, or they all were pretty much the same ? Now you've got me paranoid. I'm at 76K miles is my top end on its way out? What caused the erosion? Got any pics of the valves and seats? Pics ^^^^^,I got no idea,bike is mapped lean,but intakes were massed up also,it looks like valves and seats are not the highest quality.Maybe they don`t get along with Midwest gasoline ,,,,,,, Another thought,Honda is Mister no noise engines,maybe recommended valve lash is couple 0.01 mm too tight. Mine will be set on loose end,0.18-0.19 mm intakes and 0.24-0.25 exhaust from now on. If I were you I would do leak down test,if valves are leaking time to get dirty and lap those SOBs Quote Link to comment Share on other sites More sharing options...
Northman Posted March 6, 2007 Share Posted March 6, 2007 Cylinder head was cut 0.5mm,that plus 0.25mm removed from gasket will bring CR to about 12.1-12.2,( if stock CR is really 11.0). My stock CR measured at 10.7 Avarage, or they all were pretty much the same ? They were all pretty close, at least within .1 My engine guy said that was really good, and closer to a claimed CR that is the norm. All too commonly an actual CR will be .5 - 1 full point lower than claimed. Quote Link to comment Share on other sites More sharing options...
R1000 Posted March 6, 2007 Share Posted March 6, 2007 ....... Cylinder head was cut 0.5mm,that plus 0.25mm removed from gasket will bring CR to about 12.1-12.2,( if stock CR is really 11.0).Cams will be set to ex.100 intake 103-104,hopefully it will be much better street motor now.If no improvement,I`ve had fun doing this plus killed dead winter time.Win-win situation. O,yea,I`m also painting my XX (again) and fitting bags form ST Ducati. Did you kept the middle part of the head gasket as said before, since it has an oil restriction? Will the gasket sealing still be OK? The outer plates are profiled. Will the valve to piston clearance still be OK after milling and removal of gasket sektion? Looking forward to hear your driving impressions with the modified head, and of corse what the dyno reads if that is done. Quote Link to comment Share on other sites More sharing options...
tomek Posted March 7, 2007 Author Share Posted March 7, 2007 ....... Cylinder head was cut 0.5mm,that plus 0.25mm removed from gasket will bring CR to about 12.1-12.2,( if stock CR is really 11.0).Cams will be set to ex.100 intake 103-104,hopefully it will be much better street motor now.If no improvement,I`ve had fun doing this plus killed dead winter time.Win-win situation. O,yea,I`m also painting my XX (again) and fitting bags form ST Ducati. Did you kept the middle part of the head gasket as said before, since it has an oil restriction? Will the gasket sealing still be OK? The outer plates are profiled. Will the valve to piston clearance still be OK after milling and removal of gasket sektion? Looking forward to hear your driving impressions with the modified head, and of corse what the dyno reads if that is done. I pulled top layer out,as far as a sealing you never know for sure,but I`ve logged 2000+ track miles on my 99 R1 with the same mode with no problems.Of course if it failes it will be in the middle of the Nevada desert in August ,,,,,,and I`ll die,,,,,,,, Piston to valve clearance,I`ll check that when I degree my cams ( still waiting for sprockets from APE-my fault),but since I`ll be running stock cams and almost stock timing I`ll be shocked if there is a prob here.Stock intake has rather low lift for its dim. All this cold weather,I got really lazy,can`t just force myself to evenings in not so warm shop,,,,,,,,,plus I still got to repair some stress cracks on plastics,paint the bike,fit Duc`s panniers,,,,,I`d would say end of March when the bike is ready. Quote Link to comment Share on other sites More sharing options...
R1000 Posted March 12, 2007 Share Posted March 12, 2007 ....... Cylinder head was cut 0.5mm,that plus 0.25mm removed from gasket will bring CR to about 12.1-12.2,( if stock CR is really 11.0).Cams will be set to ex.100 intake 103-104,hopefully it will be much better street motor now.If no improvement,I`ve had fun doing this plus killed dead winter time.Win-win situation. O,yea,I`m also painting my XX (again) and fitting bags form ST Ducati. Did you kept the middle part of the head gasket as said before, since it has an oil restriction? Will the gasket sealing still be OK? The outer plates are profiled. Will the valve to piston clearance still be OK after milling and removal of gasket sektion? Looking forward to hear your driving impressions with the modified head, and of corse what the dyno reads if that is done. I pulled top layer out,as far as a sealing you never know for sure,but I`ve logged 2000+ track miles on my 99 R1 with the same mode with no problems.Of course if it failes it will be in the middle of the Nevada desert in August ,,,,,,and I`ll die,,,,,,,, Piston to valve clearance,I`ll check that when I degree my cams ( still waiting for sprockets from APE-my fault),but since I`ll be running stock cams and almost stock timing I`ll be shocked if there is a prob here.Stock intake has rather low lift for its dim. All this cold weather,I got really lazy,can`t just force myself to evenings in not so warm shop,,,,,,,,,plus I still got to repair some stress cracks on plastics,paint the bike,fit Duc`s panniers,,,,,I`d would say end of March when the bike is ready. There is also a need to check that the valve shafts and disks are perfectly straight, at least if the history of the head is unknown as with mine. After the seats where MIRA cutted, it showed up that three exhaust valves where ever so little bent when the tightness was checked by fine grit carborundum. In case the valves are just lapped into old seats, an uneven seat following the profile of a bent disk could mask this. I now have a good idea of why all intake valves have been replaced recently. Quote Link to comment Share on other sites More sharing options...
R1000 Posted April 4, 2007 Share Posted April 4, 2007 ,,,,,I`d would say end of March when the bike is ready. Any news? Quote Link to comment Share on other sites More sharing options...
tomek Posted April 5, 2007 Author Share Posted April 5, 2007 Well,,,,bike is not ready,paint booth has been really busy,I have not been able to squize in their schedule.Next week ,maybe. Having said that motor is all done,took a "naked" bike for very short spin (2 MILES) in industial part.Basically, it is totally different motor,even while idling it sounds much meaner,bark is much deeper.There is a big improvement in low and mid range,bike pulls much harder,top end feels about the same I guess,hard to tell.My recollection of XX`s top end is vouge,it has been a while since I`ve ridden that thing. Powerband is very linear,the 6-7 k rpm hit has been eliminated,it has torque everywhere.I tried to short shift,bike gains speed very fast, not unlike liter bikes,where you don`t have to use lots of revs and still blow almost everything. I`m very happy with results,my number 1 objective was wider power band and more responsive motor,it seems that I`ve achived that. Quote Link to comment Share on other sites More sharing options...
R1000 Posted April 5, 2007 Share Posted April 5, 2007 Well,,,,bike is not ready,paint booth has been really busy,I have not been able to squize in their schedule.Next week ,maybe. Having said that motor is all done,took a "naked" bike for very short spin (2 MILES) in industial part.Basically, it is totally different motor,even while idling it sounds much meaner,bark is much deeper.There is a big improvement in low and mid range,bike pulls much harder,top end feels about the same I guess,hard to tell.My recollection of XX`s top end is vouge,it has been a while since I`ve ridden that thing. Powerband is very linear,the 6-7 k rpm hit has been eliminated,it has torque everywhere.I tried to short shift,bike gains speed very fast, not unlike liter bikes,where you don`t have to use lots of revs and still blow almost everything. I`m very happy with results,my number 1 objective was wider power band and more responsive motor,it seems that I`ve achived that. OK thanks for the report. If I remember right you raised the intake runner floors according to mototune's instructions, which I didn't. In such case (you raised the floors) it seems that the stock large runners are not to bad on the Bird engine since my bike also runs very well without being weak at all below 7 krpm as before. The power transition at 7 k is not there anynore as before and t´he engine is much more linear. The main issue could have been bad valve seating for both of us, and that we now have raised the compression and lowered the squish height. I have the same feeling, I can now short shift in a totally different way than before, it doesn’t matter what gear in use as long as one cruise a low speeds, and it feels much snappier also on low rpm's at high gears. The intake roar without almost anything happening is away. The main difference between our engines after mod seems to be that the top end power on my engine has increased a lot, due to the new cams in combination with the more extensive head work with even slightly larger cross area on intake runners. They where not opened much at all, only with about 10% in certain areas, and all imperfections around seats etc was removed. The seats where also MIRA-cutted that might help some to, but I think the MIRA cutting is marginal as long as the valve to seat sealing is good. Quote Link to comment Share on other sites More sharing options...
XXSTAR Posted April 9, 2007 Share Posted April 9, 2007 I`ve redone ports a la` motoman with 30% height reduction,will see how it works.Plus I`ve cut intake guides. where is this " mototune's instructions " explain this thanks, Ron Quote Link to comment Share on other sites More sharing options...
tomek Posted April 10, 2007 Author Share Posted April 10, 2007 I`ve redone ports a la` motoman with 30% height reduction,will see how it works.Plus I`ve cut intake guides. where is this " mototune's instructions " explain this thanks, Ron What,are you a cave man ? http://mototuneusa.com/ ,you`ll need to sign up to access all the issues ,,,,,,,, Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.