VTR cam specs
#1
VTR cam specs
Just finished installing the STG 1 cams into the track VTR along with some JE 11.5:1 pistons. WHAT A BEAST. they are stock cams that have been hardwelded by WebCams, grind #189. really impressed with the power curve. seems to be no noticable loss in low end power but above 6K RPM it comes alive and pulls hard all the way to redline. i think i might get, or make, slotted sprockets and degree them in and play with the timing a little bit. depends on what i see when i get it on a dyno.
anyways i thought id compile a list of all the known cam specs for the VTR. i have yet to see most of these listed here, only across the pond, and not all in one place even there. i know i like when someone before me made it easy to find the info im looking for all in one thread so here ya go. thanks to Tony.mon for doing some of the leg work for me
Open/Close/Cam Lift (mm)/ Lobe Centre/Duration
KENT:
IN::BTDC 22/ABDC 54/10.36/106 (256 deg. duration)
EX::BBDC 60/ATDC 28/10.56/106 (268 deg. duration)
MORIWAKI:
IN::BTDC 22/ABDC 53/10.3/105.5 (255 deg. duration)
Ex::BBDC 53/ATDC 16/10.1/108.5 (249 deg. duration)
MORIWAKI: Stage II cams (unsure of the accuracy of this)
IN::BTDC ?/ABDC ?/11.506/? (271 deg. duration)
EX::BBDC ?/ATDC ?/10.49/? (256 deg. duration)
these are high lift and require heavy duty valve springs.
the main thing with these is that VE (volumetric efficiency) needs to be enhanced through things like head work, stage II exhaust, airbox modification, to take advantage of the cams. without the increase in VE, you will probably loose power. Not to worry as these are pure unobtanium.
YOSHIMURA:
IN::BTDC 17/ABDC 53/10.7/108 (250 deg duration)
EX::BBDC 55/ATDC 15/10.7/110 (250 deg. duration)
WEBCAM: Grind #189 (very similar to Stage I Mori and Yosh)
IN::BTDC 24/ABDC 48/10.28/102 (252 deg. duration)
EX::BBDC 53/ATDC 19/10.28/107 (252 deg. duration)
WEBCAM Grind #125/109 (the only grind advertised on their site)
IN::BTDC 26/ABDC 54/11.05/104 (260 deg. duration)
EX::BBDC 56/ATDC 24/10.72/106 (260 deg. duration)
this cam profile is more of a halfway between Stage 1 and Stage 2. it is a fairly top end oriented cam and does require heavy duty valve springs which are available through webcams
Stock
IN::BTDC 20/ABDC 45/?/102.5 (245 deg. duration)
EX::BBDC 50/ATDC 15/?/107.5 (245 deg. duration)
Companys like WebCams and others will take stock cams and re-profile them to any specs you want really. to my knowledge there is basically no new aftermarket cams available (Mori, Yosh, etc...) so short of guys pulling out there cams and selling them, re-profiled custom cams are really the only option.
The quality of the regrind cams i have from webcams is top notch and i have heard nothing but good things about the company. i have heard of other smaller shops doing a regrind and in time the cams wear and become smaller so id choose a reputable company for the job.
STG I cams, from the research ive done, seem to net anywhere from 5-10 hp depending on the specific cams, and the engine in which they are being used in. they are reliable and give a good boost without sacrificing drivability or engine life.
STG II cams add a few more hp and usually in the higher RPMs but at the expense of longevity.
anyways i thought id compile a list of all the known cam specs for the VTR. i have yet to see most of these listed here, only across the pond, and not all in one place even there. i know i like when someone before me made it easy to find the info im looking for all in one thread so here ya go. thanks to Tony.mon for doing some of the leg work for me
Open/Close/Cam Lift (mm)/ Lobe Centre/Duration
KENT:
IN::BTDC 22/ABDC 54/10.36/106 (256 deg. duration)
EX::BBDC 60/ATDC 28/10.56/106 (268 deg. duration)
MORIWAKI:
IN::BTDC 22/ABDC 53/10.3/105.5 (255 deg. duration)
Ex::BBDC 53/ATDC 16/10.1/108.5 (249 deg. duration)
MORIWAKI: Stage II cams (unsure of the accuracy of this)
IN::BTDC ?/ABDC ?/11.506/? (271 deg. duration)
EX::BBDC ?/ATDC ?/10.49/? (256 deg. duration)
these are high lift and require heavy duty valve springs.
the main thing with these is that VE (volumetric efficiency) needs to be enhanced through things like head work, stage II exhaust, airbox modification, to take advantage of the cams. without the increase in VE, you will probably loose power. Not to worry as these are pure unobtanium.
YOSHIMURA:
IN::BTDC 17/ABDC 53/10.7/108 (250 deg duration)
EX::BBDC 55/ATDC 15/10.7/110 (250 deg. duration)
WEBCAM: Grind #189 (very similar to Stage I Mori and Yosh)
IN::BTDC 24/ABDC 48/10.28/102 (252 deg. duration)
EX::BBDC 53/ATDC 19/10.28/107 (252 deg. duration)
WEBCAM Grind #125/109 (the only grind advertised on their site)
IN::BTDC 26/ABDC 54/11.05/104 (260 deg. duration)
EX::BBDC 56/ATDC 24/10.72/106 (260 deg. duration)
this cam profile is more of a halfway between Stage 1 and Stage 2. it is a fairly top end oriented cam and does require heavy duty valve springs which are available through webcams
Stock
IN::BTDC 20/ABDC 45/?/102.5 (245 deg. duration)
EX::BBDC 50/ATDC 15/?/107.5 (245 deg. duration)
Companys like WebCams and others will take stock cams and re-profile them to any specs you want really. to my knowledge there is basically no new aftermarket cams available (Mori, Yosh, etc...) so short of guys pulling out there cams and selling them, re-profiled custom cams are really the only option.
The quality of the regrind cams i have from webcams is top notch and i have heard nothing but good things about the company. i have heard of other smaller shops doing a regrind and in time the cams wear and become smaller so id choose a reputable company for the job.
STG I cams, from the research ive done, seem to net anywhere from 5-10 hp depending on the specific cams, and the engine in which they are being used in. they are reliable and give a good boost without sacrificing drivability or engine life.
STG II cams add a few more hp and usually in the higher RPMs but at the expense of longevity.
#3
Looking at all the specs posted, it seems to me that the #189 grind would be about best overall. I found my Yosh cams a bit noisy (likely from increased lift) and would imagine they are probably borderline for needing stiffer springs. The 189 has a bit more lift than the Moris (good for acceleration) and decent duration too. Fine choice overall, looking forward to the dyno data.......
#4
Lloydie, where in the world did you get yosh cams?? new or used? nice score.
Mik, yea yhe yosh cams tip toe on the limit of needing new springs. Roger D. told me anything 11.00 mm and higher needs springs so the yosh cams cut it close. im very happy with the 189 grind. would i rather have a set of true Moriwakis? yes but considering the only line i have on a set is $1500, these regrinds will do me just fine. i may be getting down to the dyno today.
Mik, yea yhe yosh cams tip toe on the limit of needing new springs. Roger D. told me anything 11.00 mm and higher needs springs so the yosh cams cut it close. im very happy with the 189 grind. would i rather have a set of true Moriwakis? yes but considering the only line i have on a set is $1500, these regrinds will do me just fine. i may be getting down to the dyno today.
#5
they were miks tho i can only use the inlet cams as mik broke one of the ex cams and yoshi no longer make or have any in stock i did ask yoshi .
one day if i can get some standard ex remade to match the yosis i will but just the inlets on there own should work well
one day if i can get some standard ex remade to match the yosis i will but just the inlets on there own should work well
#6
Ahhh yes the infamous snapping of the precious yosh cams. I know its cheap (around $250 usd) for webcams to do just 2 cams. Fortunately its the stock exhaust cams that are a bit hotter.
#7
I've got a set brand new still in the box. I've tried to sell them but, sadly, nobody wants to buy them! Instead they sit on the shelf waiting for the non-existent free time to allow me to put them in my own bike.
#8
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09-18-2012 10:37 AM