V&H Billet Clutch Basket Question

[blowerbike]

You're splitting hairs here. Guys power shifting their 100+ hp motorcycles basically "are" racers, whether on a track or street.

i did not know that this was a goldwing forum.

my point is.......
if a person has there dick skinners in there shimming and welding the stock basket..
why not install the H/D backing plate kit while your there????
it is the same...maybe even less labor than the shimming stuff.
so less than 150 bucks would let a person go from doing a band aid job to correct/professional H/D clutch basket that if a person chooses to run hard...
they can without worries about crap blowing through the cases when there stock basket fly's apart..
i have seen several pipe/jet kitted 1100/1150's with ruined cases from a "non racer" having "blown the carbon out".

 

[blowerbike]

Excuse my ignorance here, but I'm curious how the basket is constructed and how the power is transferred... If the gear on the back is riveted onto the basket, where do the springs come into play if the power is transmitted through the rivets? or are the holes the rivets go through slotted to allow the basket to rotate and then the springs take up the load and cushion the power as it's transmitted from the crank to the trans?

your clutch basket is the same principal as your rear wheel cush drive.
what loosen's everything is the side load from the angle primary gears.
suzuki used the angle gears because they are quiet...they never considered the side load issues these gears would create.
old kawi's don't have this problem...why?
because they have straight cut gears installed from the factory.
yes the old kawi's are noisy... but they won't blow the basket apart even when modified.
if you ever come upon a cheap GS basket...buy it and take it apart.
you will see how everything works.

 

[Turtleface]

I love powershifting my 1100E, and running her right up to 9 grand. Didn't do it very often, and didn't miss-shift or over-rev.

Still, it's probably why my clutch basket started knocking. Thankfully, I caught it before it flew apart. I'm waiting on it to come back from APE, with my new HD kit installed, along with a new hub nut, fibers and springs. Kinda spendy, but it's nice knowing that I won't have to touch it ever again...until I get around to building a bigger motor, anyways.

 

[rapidray]

Did you get the "extra plate" clutch kit that will gouge the crap out of your hub? Ray.

 

[posplayr]

Did you get the "extra plate" clutch kit that will gouge the crap out of your hub? Ray.

Ray is trying to say is the thinner fibers cut into the hub more causing clutch drag.

 

[Guest]

old kawi's don't have this problem...why?
because they have straight cut gears installed from the factory.
yes the old kawi's are noisy... but they won't blow the basket apart even when modified.

I have noticed a few times on this forum that people have mentioned getting straight cut gears installed. I can see that it must be much more robust and is good insurance.

However I would like to know when the situation changes from "nice to have" to "must have". Is it the amount of torque or HP? For example ... over X amount of HP, get straight cut gears; under X amount of HP you are OK with angled gears?

Thanks!

 

[Nessism]

Helical gears are stronger, however they create side load which is bad for the clutch in our application so that outweighs the benefit for guys with high hp engines, or for guys that ride their bikes hard.

 

[Guest]

Helical gears are stronger, however they create side load which is bad for the clutch in our application so that outweighs the benefit for guys with high hp engines, or for guys that ride their bikes hard.

I thought it was a noise thing.

 

[posplayr]

I thought it was a noise thing.

Nice write up on gears; Helical are stronger and quieter than spur gears but Helical have more friction and thrust

http://en.wikipedia.org/wiki/Gear

The angled teeth engage more gradually than do spur gear teeth causing them to run more smoothly and quietly. With parallel helical gears, each pair of teeth first make contact at a single point at one side of the gear wheel; a moving curve of contact then grows gradually across the tooth face to a maximum then recedes until the teeth break contact at a single point on the opposite side. In spur gears teeth suddenly meet at a line contact across their entire width causing stress and noise. Spur gears make a characteristic whine at high speeds and can not take as much torque as helical gears. Whereas spur gears are used for low speed applications and those situations where noise control is not a problem, the use of helical gears is indicated when the application involves high speeds, large power transmission, or where noise abatement is important. The speed is considered to be high when the pitch line velocity exceeds 25 m/s.[5]
A disadvantage of helical gears is a resultant thrust along the axis of the gear, which needs to be accommodated by appropriate thrust bearings, and a greater degree of sliding friction between the meshing teeth, often addressed with additives in the lubricant.

 

[rapidray]

Explain to me then why in EVERY high horse drag car & motorcycle transmission uses straight cut gears in the transmissions? Pro Stock cars, at 500 cubic inches ae making almost 1500 hp & OVER 1000 lbs of torque & ALL use straight cut gears. Same with transmissions in Pro Stock bikes & Top Fuel & Funny Bikes. Ray.

 

[sam78gs750]

so... ummm... I beat the hell out of my bike. Run it close to redline, powershift all the time.... should I be worried about my clutch blowing up in a huge mushroom cloud here? Angled gears???

 

[posplayr]

Explain to me then why in EVERY high horse drag car & motorcycle transmission uses straight cut gears in the transmissions? Pro Stock cars, at 500 cubic inches ae making almost 1500 hp & OVER 1000 lbs of torque & ALL use straight cut gears. Same with transmissions in Pro Stock bikes & Top Fuel & Funny Bikes. Ray.

Ray I know that is a rhetorical question, but I'll try and explain the apparent paradox anyway.


a.) The straight cut gears are used primarily because they have much less drag than a Helical gear. The Helical gear faces slide against one another when they meet and there is more friction (I can't quantify that but I'm sure if there are some ME's here they covered that in class).

b.) The straight cut gears have no side force thrust, which again reduces frictional forces (i.e. on thrust bearings)

a.) and b.) make straight cut gears more efficient (less lost torque in friction)

c.) The helical gears are quieter, I think if you back up your car you will hear a reverse spur gear making extra noise. On the GS the smaller gear on the clutch hub is not that small in relation to the driving gear on the crank so straight cut GS gears as not as bad from a noise perspective. Of course with 1500 hp who could tell ?

d.) Finally the issue of strength. That is more complicated but all else being equal, the helical gear can handle more torque because there is more effective thickness to the helical tooth v.s the spur gear tooth. Stiffness normally increases to a power (like third power) of thickness and the helical gears as at an angle at the point of mesh so it is logical to assume there is a higher stiffness and the gear teeth will sustain a higher total load assuming thrust can be dealt with.

e.) There is another issue of fatigue life, where the helical gears are more likely to encounter high mileage and the 1500 hp machines you are speaking of never likely get to 100K miles. So the cumulative stress of the straight cut gears see if much less than the helical cut.

Jim

 

[Nessism]

Yea, what Jim wrote...

Helical gear tooth size is larger, which makes it stronger. The gradual tooth engagement also makes it quieter and smoother. Problem is thrust loads.

 

[gs road racer]

Yea, what Jim wrote...

Helical gear tooth size is larger, which makes it stronger. The gradual tooth engagement also makes it quieter and smoother. Problem is thrust loads.

Ditto that Ed the engineers made a compromise in these motors that way. Unfortunately for us that's created some problems with the thrust even in stock form. It did make them quieter until the clutch basket damper springs break and make a hell of a racket...sounds like it's gonna jump out and bite ya! The mention of very high horsepower drives using straight cut gears because of strength? NO because the thrust loads would be unmanageable.Well maybe not no in fact the helically cut gear has less engagement/contact surface then the straight cut gear (this is an argument that should be taken as a question to an engineer).The helical gear transmits shock better , but transmits it as thrust.

 

[blowerbike]

so... ummm... I beat the hell out of my bike. Run it close to redline, powershift all the time.... should I be worried about my clutch blowing up in a huge mushroom cloud here? Angled gears???

unless you own a large CC roller bearing GS.....
insert bearing models do not apply and 77-79 GS 750's have straight cut primarys and are bullet proof.
i have used the 750 gears w/ 300 + or - a few HP..
bullet proof!

this topic has wondered off its path.

 

[sam78gs750]

unless you own a large CC roller bearing GS.....
insert bearing models do not apply and 77-79 GS 750's have straight cut primarys and are bullet proof.
i have used the 750 gears w/ 300 + or - a few HP..
bullet proof!

Very well....I'll continue to ride it hard with no clutch mods. Thanx for the info and peace of mind

this topic has wondered off its path.

given my previous comment I obviously have nothing to contribute to this topic... I just got a little shook by all this talk about powershifting and blowing out clutch baskets Sorry about the thread jack. Back to the V&H clutch basket, what he'll need and what it'll cost.

 

[TheCafeKid]

so... ummm... I beat the hell out of my bike. Run it close to redline, powershift all the time.... should I be worried about my clutch blowing up in a huge mushroom cloud here? Angled gears???

No, your bike came from the factory with straight cut gears. Thus, no side load.. the 77-79 750 TO MY KNOWLEGE, is the ONLY GS with this gear set stock..Maybe the 1150? But I dunno..

 

[Guest]

i have used the 750 gears w/ 300 + or - a few HP..
bullet proof!

How is this done? Are the gears removed from the 750 crank and clutch basket, and then installed (welded I guess) on the 1100 items?

 

[rapidray]

1150 has helical clutch hub gears too. Ray.

 

[rapidray]

How is this done? Are the gears removed from the 750 crank and clutch basket, and then installed (welded I guess) on the 1100 items?

Yes, the 750 clutch hub gear & crank gear are installed on the 1100 clutch hub & crank. I just did a 1229 street motor for streetracer1150 with 750 gears & there is some clearancing that needs to be done inside the 1100 cases to get the clutch gear to clear. About 30 minutes work. BIG difference in clutch tunability on a high hp motor but you also use 5-7 FEWER teeth on the rear sprocket so less chain to spin! Ray.