Stage 2 Cam Valve Springs

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freeridenick
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Re: Stage 2 Cam Valve Springs

Post by freeridenick »

Chris58 wrote: Mon Dec 10, 2018 10:02 pm Is it just me.. or do these degree numbers seem very high.
Im thinking that its because its measured at 40thou instead of the standard 50thou
I've still got the instructions for my Yoshi Stg1 cams so I'll have a look for a comparison. There's a post on the Superhawk forum with the figures too I think.

Worth thinking about bigger valves too; +1mm intake and +0.5mm exhaust.
mik_str
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Re: Stage 2 Cam Valve Springs

Post by mik_str »

freeridenick wrote: Tue Dec 11, 2018 12:28 pm
Chris58 wrote: Mon Dec 10, 2018 10:02 pm Is it just me.. or do these degree numbers seem very high.
Im thinking that its because its measured at 40thou instead of the standard 50thou
I've still got the instructions for my Yoshi Stg1 cams so I'll have a look for a comparison. There's a post on the Superhawk forum with the figures too I think.

Worth thinking about bigger valves too; +1mm intake and +0.5mm exhaust.
I`ll spare y0u the work, got them moemorized:

both Yosh cam have identical lobe profiles, ie. 250 deg duration, 10.7mm lift, LCs are 108 IN and 110 EX
99 VTR1000F Firestorm, a.k.a. The Carbon Express
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Chris58
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Re: Stage 2 Cam Valve Springs

Post by Chris58 »

freeridenick wrote: Tue Dec 11, 2018 12:28 pm
Chris58 wrote: Mon Dec 10, 2018 10:02 pm Is it just me.. or do these degree numbers seem very high.
Im thinking that its because its measured at 40thou instead of the standard 50thou
I've still got the instructions for my Yoshi Stg1 cams so I'll have a look for a comparison. There's a post on the Superhawk forum with the figures too I think.

Worth thinking about bigger valves too; +1mm intake and +0.5mm exhaust.
I would love to do biggee valves but they are out of the budget for now. plus, the last leak down test results were also extremly good, only 4%.

also not sure how big of difference they'd make, pretty sure Ive read on here that only +.5 on the exhaust yeilded any results...
but my brain says that +1 on intake couldnt hurt
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VT1000r
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Re: Stage 2 Cam Valve Springs

Post by VT1000r »

8541Hawk wrote: Mon Dec 10, 2018 12:07 am Well all good info but what I see as the most important factor here is coil bind.

The stocks springs would almost certainly bind with STG 2 cams IMHO.
I have this opinion because all the high lift cam options have spec'd replacement springs.

Even with big cams, hi comp pistons, head work and whatever else you can throw at it you are not going to raise the RPM for the peak power by all that much.
Again in my opinion, no matter what you do, the power peak will be below 10K RPM. So in that case the only real need for replacement springs would be to get more space between the coils.
The stock rev limiter kicks in at 10.3K RPM. So we know the springs can run at that RPM all day with no issues.

Sorry to go on but, again in my opinion, if you try to run STG2 cams with stock springs there is a good chance of something going bang.

Is it possible to raise the peak power past 10k on the vtr1000
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freeridenick
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Re: Stage 2 Cam Valve Springs

Post by freeridenick »

VT1000r wrote: Sat Jan 19, 2019 8:05 am
Is it possible to raise the peak power past 10k on the vtr1000
Not in my experience, peak has always been around 9k regardless of engine tune. Although I'm using the stock ECU.

Why would you want to is my question? Peak power right up close to the limiter is not much use.
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fabiostar
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Re: Stage 2 Cam Valve Springs

Post by fabiostar »

im running the modded ECU and its still making its best horsepower from 7 to 9.5 which is safe enough. a big twin of that age revving higher scares me :)
the older i get,the faster i was :lol:
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VT1000r
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Re: Stage 2 Cam Valve Springs

Post by VT1000r »

freeridenick wrote: Sat Jan 19, 2019 8:17 am
VT1000r wrote: Sat Jan 19, 2019 8:05 am
Is it possible to raise the peak power past 10k on the vtr1000
Not in my experience, peak has always been around 9k regardless of engine tune. Although I'm using the stock ECU.

Why would you want to is my question? Peak power right up close to the limiter is not much use.
i was wondering because the morwawki vtr stg3 are make 150+rwhp so they have to be spinning some more rpms or making alot of torque below 10K right?
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Chris58
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Re: Stage 2 Cam Valve Springs

Post by Chris58 »

I think a STG 3 vtr uses a forged crank to handle high rpm and is very well balanced.. and even then probably doesn't rev much past 10k

I wonder if the stg 3 rev ceiling is posted here somewhere..
tony.mon
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Re: Stage 2 Cam Valve Springs

Post by tony.mon »

The worry for me would be downshifting at too high revs and over revving that way, so whatever rev limiter you have you can find yourself at higher revs than planned.

So a healthy safety margin seems a good idea, as is a slipper clutch....

The coil binding would be a concern, but measuring mine with modified cams and high comp pistons still gave 3mm piston-to-valve clearance, so that won't be a limiting factor.
But I'd still suggest measuring clearance for yourself with your own components, my cams were only just over 1mm higher lift.
It's not falling off, it's an upgrade opportunity.
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VT1000r
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Re: Stage 2 Cam Valve Springs

Post by VT1000r »

Chris58 wrote: Sat Jan 19, 2019 5:48 pm I think a STG 3 vtr uses a forged crank to handle high rpm and is very well balanced.. and even then probably doesn't rev much past 10k

I wonder if the stg 3 rev ceiling is posted here somewhere..
i am very interested in the specs of the stage 3 bike ive been digging around and haven't been able to find specs on the stage 3, however i have found a little on the stage 2 morowaki rain track bike original, but i dont think they stated rev ceiling. If you come across any info on stg3 please let me know.
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Chris58
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Re: Stage 2 Cam Valve Springs

Post by Chris58 »

VT1000r wrote: Sat Jan 19, 2019 6:50 pm
Chris58 wrote: Sat Jan 19, 2019 5:48 pm I think a STG 3 vtr uses a forged crank to handle high rpm and is very well balanced.. and even then probably doesn't rev much past 10k

I wonder if the stg 3 rev ceiling is posted here somewhere..
i am very interested in the specs of the stage 3 bike ive been digging around and haven't been able to find specs on the stage 3, however i have found a little on the stage 2 morowaki rain track bike original, but i dont think they stated rev ceiling. If you come across any info on stg3 please let me know.
There is quite a bit of Info on the forum from Roger Ditchfield about stg 3 bike... he was involved in building them.
Ill search around the forum and see what I can dig up... I dont recall him ever stating the redline.
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VT1000r
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Re: Stage 2 Cam Valve Springs

Post by VT1000r »

Chris58 wrote: Sat Jan 19, 2019 7:15 pm
VT1000r wrote: Sat Jan 19, 2019 6:50 pm
Chris58 wrote: Sat Jan 19, 2019 5:48 pm I think a STG 3 vtr uses a forged crank to handle high rpm and is very well balanced.. and even then probably doesn't rev much past 10k

I wonder if the stg 3 rev ceiling is posted here somewhere..
i am very interested in the specs of the stage 3 bike ive been digging around and haven't been able to find specs on the stage 3, however i have found a little on the stage 2 morowaki rain track bike original, but i dont think they stated rev ceiling. If you come across any info on stg3 please let me know.
There is quite a bit of Info on the forum from Roger Ditchfield about stg 3 bike... he was involved in building them.
Ill search around the forum and see what I can dig up... I dont recall him ever stating the redline.
thanks for that, i look into mr.roger.
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fabiostar
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Re: Stage 2 Cam Valve Springs

Post by fabiostar »

the stage 3 parts have all dried up im afraid, even the 2 parts are getting hard to find, but as has been said the 3 runs a forged crank and i would say would need regular rebuilds if used on the road.. :eek2
the older i get,the faster i was :lol:
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VT1000r
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Re: Stage 2 Cam Valve Springs

Post by VT1000r »

fabiostar wrote: Sat Jan 19, 2019 11:44 pm the stage 3 parts have all dried up im afraid, even the 2 parts are getting hard to find, but as has been said the 3 runs a forged crank and i would say would need regular rebuilds if used on the road.. :eek2
Awesome, thanks for the info, it's a shame the parts have dried up though it was an amazing bike the stg3 I would of chose it over a Ducati panagale 1299 anyday.
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freeridenick
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Re: Stage 2 Cam Valve Springs

Post by freeridenick »

The race bikes using Mori ECUs had no rev limit, ask Mik_str.
IIRC the photos I've seen show a 'redline' of around 10,700. There's a post of mime on here with a pdf of an article on the Mori endurance bike that shows it.
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