Topic: Geared Primary Drive

[Captain]

I am sorta thinking..
Racing a monster motor and changing the Hyvo every race.
 I am thinking 5 to 8 or ten races.  3 hours minimum  to change it out. Adds up fast looks like 1500 to 3000 a season just to keep chains in it......ouch...

 I got the point that it was "every race" not every meeting.
  The last time we ran a chain it lasted for practice and qualifying, one race and two laps of the next (the chain was brand new HD race spec and so was the manual tensioner).
Admittedly this was at Spa in Belgium and a sustained high speed track which amplified the effects but it was the final confirmation of the ever reducing chain life we were experiencing with each increase of RPM and HP.   The resulting damage of this final failure was approx 50% of the engine destroyed (and we got away lightly). To repeat and remain with a chain and accept the risk is totally unrealistic and foolish unless both HP and RPM are reduced. To have arrived at the point that we have this problem is actually a success and from which I will not retreat and so the Gear Drive was born.
The point here is that Silent Chains have a speed limit and when combined with high HP and high RPM are just not viable for any serious durability expectations.

 Captain

[MessnerMoto]

Anything new?

I don't have engine to put it in. I reached to several members if they want to join in. There was no real interest.

Anything new?

+1 ??

+1   900 idler
😀

idler carrier and 900 idler can be made easily also

[T1m32sh1n3]

Hell, I'd like to try it in a street engine.

[Medyo Bastos]

Hell, I'd like to try it in a street engine.

me too

[Tracksnblades1]

Hell, I'd like to try it in a street engine.

me too

Anything new?

I don't have engine to put it in. I reached to several members if they want to join in. There was no real interest.

Anything new?

+1 ??

+1   900 idler
😀

idler carrier and 900 idler can be made easily also

Mirko,

I'm interested in a 900 crank version for the street. Too old to RACE, then it would be a struggle just to be below average.....😩  I need to p...m... you anyway. I'll try Monday after I get back from Lincoln Nebraska
Thanks for your Toil Mirko..
👍

[MessnerMoto]

pm who is interested

[dragracer]

If I could afford it, I would certainly throw my hat in the ring for a set to install in a drag race engine. Cost is a factor but i'll send a PM anyway.


\

pm who is interested

[scottly]

Hell, I'd like to try it in a street engine.

me too

Why?

[T1m32sh1n3]

Why not

[scottly]

First, the stock primary chain is adequate for a street bike for over 100,000 miles. Second, to use the gear drive, you must first switch to the Hy-vo, or Silent type chain drive crankshaft and primary shaft, which is even stronger than the original primary chain. As Captain alluded to, in his case chains can't handle the extreme RPMs he is running. You will not see 14,000+ RPM on a street bike.  

[T1m32sh1n3]

Good points

[Don R]

 I am interested too.

[teebee67]

Me too.

[MessnerMoto]

First, the stock primary chain is adequate for a street bike for over 100,000 miles. Second, to use the gear drive, you must first switch to the Hy-vo, or Silent type chain drive crankshaft and primary shaft, which is even stronger than the original primary chain. As Captain alluded to, in his case chains can't handle the extreme RPMs he is running. You will not see 14,000+ RPM on a street bike.

that 100k miles will depend on how you drive it.

Ok I see there is interest

the best way how to proceed is that I finish all the parts and then send them to person who is closest to actually testing it

[gschuld]

I have interest in this also once it has been tested.

George

[T1m32sh1n3]

I'm far from ready

[Don R]

 I'm following what Tracksnblades1 does.

[MessnerMoto]

Is there anybody out there how is very close to finishing then engine(testing) and also would use CB750A(auto) crank ?

I can finish and provide system fast in that case.

[MessnerMoto]

I am sorta thinking..
Racing a monster motor and changing the Hyvo every race.
 I am thinking 5 to 8 or ten races.  3 hours minimum  to change it out. Adds up fast looks like 1500 to 3000 a season just to keep chains in it......ouch...

 I got the point that it was "every race" not every meeting.
  The last time we ran a chain it lasted for practice and qualifying, one race and two laps of the next (the chain was brand new HD race spec and so was the manual tensioner).
Admittedly this was at Spa in Belgium and a sustained high speed track which amplified the effects but it was the final confirmation of the ever reducing chain life we were experiencing with each increase of RPM and HP.   The resulting damage of this final failure was approx 50% of the engine destroyed (and we got away lightly). To repeat and remain with a chain and accept the risk is totally unrealistic and foolish unless both HP and RPM are reduced. To have arrived at the point that we have this problem is actually a success and from which I will not retreat and so the Gear Drive was born.
The point here is that Silent Chains have a speed limit and when combined with high HP and high RPM are just not viable for any serious durability expectations.

 Captain

Captain can we get one advice. Do you think that idler sprocket bearings should get feed of oil directly from oil pump or there is enough oil around floating and bathing the bearings ?

[Captain]

I am sorta thinking..
Racing a monster motor and changing the Hyvo every race.
 I am thinking 5 to 8 or ten races.  3 hours minimum  to change it out. Adds up fast looks like 1500 to 3000 a season just to keep chains in it......ouch...

 I got the point that it was "every race" not every meeting.
  The last time we ran a chain it lasted for practice and qualifying, one race and two laps of the next (the chain was brand new HD race spec and so was the manual tensioner).
Admittedly this was at Spa in Belgium and a sustained high speed track which amplified the effects but it was the final confirmation of the ever reducing chain life we were experiencing with each increase of RPM and HP.   The resulting damage of this final failure was approx 50% of the engine destroyed (and we got away lightly). To repeat and remain with a chain and accept the risk is totally unrealistic and foolish unless both HP and RPM are reduced. To have arrived at the point that we have this problem is actually a success and from which I will not retreat and so the Gear Drive was born.
The point here is that Silent Chains have a speed limit and when combined with high HP and high RPM are just not viable for any serious durability expectations.

 Captain

Captain can we get one advice. Do you think that idler sprocket bearings should get feed of oil directly from oil pump or there is enough oil around floating and bathing the bearings ?

  The operational loads are too high (even using hybrid ceramic bearings) not to have a dedicated oil feed for both cooling and lubrication. In my DOHC install I do this by drilling a small hole (.8mm) in the main oil passage as it passes by the idler. The resulting jet is directed at the idler gear bearings.

 Captain

[Tracksnblades1]

I am sorta thinking..
Racing a monster motor and changing the Hyvo every race.
 I am thinking 5 to 8 or ten races.  3 hours minimum  to change it out. Adds up fast looks like 1500 to 3000 a season just to keep chains in it......ouch...

 I got the point that it was "every race" not every meeting.
  The last time we ran a chain it lasted for practice and qualifying, one race and two laps of the next (the chain was brand new HD race spec and so was the manual tensioner).
Admittedly this was at Spa in Belgium and a sustained high speed track which amplified the effects but it was the final confirmation of the ever reducing chain life we were experiencing with each increase of RPM and HP.   The resulting damage of this final failure was approx 50% of the engine destroyed (and we got away lightly). To repeat and remain with a chain and accept the risk is totally unrealistic and foolish unless both HP and RPM are reduced. To have arrived at the point that we have this problem is actually a success and from which I will not retreat and so the Gear Drive was born.
The point here is that Silent Chains have a speed limit and when combined with high HP and high RPM are just not viable for any serious durability expectations.

 Captain

Captain can we get one advice. Do you think that idler sprocket bearings should get feed of oil directly from oil pump or there is enough oil around floating and bathing the bearings ?

  The operational loads are too high (even using hybrid ceramic bearings) not to have a dedicated oil feed for both cooling and lubrication. In my DOHC install I do this by drilling a small hole (.8mm) in the main oil passage as it passes by the idler. The resulting jet is directed at the idler gear bearings.

 Captain

Captain,
Do you use a single or two bearing set up In your idler gear.  Not to purposely divulge any of your secrets, but, did you employ oil jet piston cooling on your Max-effort Dohc engine..?
Thanks and for your service too.
TB1

[Captain]

 Idler has two bearings and an oil feed via a jet as stated earlier.
 As for the piston cooling................No it relies on splash and I monitor the pistons closely and to date there has been no evidence of any problem.   Also I am running 3D ignition and as this reduces piston temps it is obviously a factor.

 Captain

[MessnerMoto]

I think I agreed with eli that he will test the solution. He has everything ready including CB750A crank.

My plan is to ship all the components in one month time to eli.

For people interested in CB900 crank.

I realized(forgot) that I need to make also primary sprocket dumber specially for CB900 crank. It is just matter of different number of tooth because cb750/cb750A has 24 tooth on sprocket vs cb900 28 tooth.
So I will not loose time there.

for my build I will use cb900 crank actually... but different topic...

I am sorta thinking..
Racing a monster motor and changing the Hyvo every race.
 I am thinking 5 to 8 or ten races.  3 hours minimum  to change it out. Adds up fast looks like 1500 to 3000 a season just to keep chains in it......ouch...

 I got the point that it was "every race" not every meeting.
  The last time we ran a chain it lasted for practice and qualifying, one race and two laps of the next (the chain was brand new HD race spec and so was the manual tensioner).
Admittedly this was at Spa in Belgium and a sustained high speed track which amplified the effects but it was the final confirmation of the ever reducing chain life we were experiencing with each increase of RPM and HP.   The resulting damage of this final failure was approx 50% of the engine destroyed (and we got away lightly). To repeat and remain with a chain and accept the risk is totally unrealistic and foolish unless both HP and RPM are reduced. To have arrived at the point that we have this problem is actually a success and from which I will not retreat and so the Gear Drive was born.
The point here is that Silent Chains have a speed limit and when combined with high HP and high RPM are just not viable for any serious durability expectations.

 Captain

Captain can we get one advice. Do you think that idler sprocket bearings should get feed of oil directly from oil pump or there is enough oil around floating and bathing the bearings ?

  The operational loads are too high (even using hybrid ceramic bearings) not to have a dedicated oil feed for both cooling and lubrication. In my DOHC install I do this by drilling a small hole (.8mm) in the main oil passage as it passes by the idler. The resulting jet is directed at the idler gear bearings.

 Captain

Thanks Captain. I am planing to add feed from return line. I will use 0.8mm like you recommended.
But is there a restriction on the other side or is it also 0.8mm? And because there are two bearings do you feed oil just on one side of two bearings combination ? 

 

[Captain]

 
From one side is enough as long as the oil Jet is directed low enough as centrifugal force flings it outwards. This also sends it towards the other bearing.
It has certainly been sufficient in my experience.

 Captain

[MessnerMoto]

From one side is enough as long as the oil Jet is directed low enough as centrifugal force flings it outwards. This also sends it towards the other bearing.
It has certainly been sufficient in my experience.

 Captain

thanks! I have everything now