theTRUTH

See cars and bikes being built for the salt

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gennyshovel
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Re: theTRUTH

Post by gennyshovel »

Low 150's, by memory
Tiny DLRA# 484
Postiebike Racing , created & funded by TwoBob Engineering
Hoofhearted
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Re: theTRUTH

Post by Hoofhearted »

I'm trying to remember but my sidecar weighs around 475 lbs. There is no flop or handing problems. Truth is it doesn't want to turn. Turn out at Bonneville at 60 or so and let go of the bars and they immediately straighten. Some years ago at El Mirage the kill switch activated and as it was a good run I reached over with my left hand and held the switch on. Straight as a die.

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russelllowe
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Re: theTRUTH

Post by russelllowe »

Hi Grumm and Walkingpace; my CB750 motor has been sitting on a trolley out of the frame for over a year now, so it wont be hard to take a look at the sumping valve in the oil pump ... be interesting to see if that is the culprit. With heavy oil in it (60 grade) it would start off with about 50psi and then plummet as it warmed up.

Stayt'ie; I'll have some training wheels to help at low speed, and I'm predicting it's going to be a bit of a pig to move around in the pits and the start line, but it's really the high speeds that I'm looking to optimize for.

Grumm; yeah, rule 7.B.8 says "265 MPH+ Contestants shall use LSR or other tires as approved by the Motorcycle Technical Committee, Section 9."

But you might have meant that 265mph is a bit optimistic ... also true.

Here's a semi interesting fact; the block of the LS3 is about 60mm narrower that my mate Paul's CBR1100 Blackbird ... I'll have the sprocket on the drive side and the harmonic balancer on the water pump side poking out further, but that surprised me. Yes it's a big motor, but not that big ...

Cheers!
russelllowe
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Re: theTRUTH

Post by russelllowe »

Hoofhearted; the LS3 weighs about 175kg by itself ... (475lb is 215kg). At a guess I recon I might get the whole lot under 300kg (660lb). Were you carrying ballast?

(Yes, just saw your posts on the jockeyjournal: http://www.jockeyjournal.com/forum/show ... 268&page=8 ... re tires: I used Firestone classic balloon tires on my CB750 racing at BUB; no speed rating on those tires but BUB's rules state it's ultimately at the riders discretion what tires they use ... at least it was in 2013 and 2014. I went 109.95mph on them and was perfectly happy to do so)

Cool photo by the way!

Cheers
Hoofhearted
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Re: theTRUTH

Post by Hoofhearted »

I have ballast in the sidecar wheel area. The sidecar wheel suspension ( I was advised by Tom Evans when I went to a solid aluminum sidecar wheel to use suspension) is made from 1/2" and 3/8" steel along with about 30 lbs. of leaf in order to meet the 10% of the OA weight be on the sidecar wheel. I was going to ask if you had thought about putting a sidecar on it? Has a lot of advantages. You don't have to hold it up in line. You can't fall off it. And sidecars are cool.

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grumm441
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Re: theTRUTH

Post by grumm441 »

I don't know if you noticed the VW powered bike in the pits. It had a low center of gravity and a long steering angle.
It also spent a lot of time lying on it's side.
Bill, I like what you've done with the sidecar wheel supports. was it worth any MPH
G
They make it
I make it work
Hoofhearted
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Re: theTRUTH

Post by Hoofhearted »

I'm not 100% sure. I know it didn't do any harm. I saw a video on land racing about drag. Round versus aerofoil. They aren't pure but 129 to 131 with no other changes can't be sneezed at.
Don't cry because its over. Smile because it happened.
russelllowe
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Re: theTRUTH

Post by russelllowe »

Hi Graham, yes, I did notice the VW powered bike (but not on it's side!) ... you think 45 degrees is too much? Any suggestions re a reasonable range given what you've see out on the lake?

Hi again Walkingpace, I'm back to focusing on the clutch again; I think it's the last big design issue to solve (steering rake notwithstanding). I've been looking at the quartermaster 7.25" multiplate clutches like you are using and, if you have time, I have a few questions:

Are you using a 2 or 3 plate version?
I can't find anywhere that says how much power/torque they are capable of holding ... have you seen figures mentioned anywhere?
Did you buy it direct from Quarter Master in the states or from another supplier there or here? (It looks like you can get good savings buying from Jeg's for example http://www.jegs.com/i/Quarter-Master/64 ... 3/10002/-1...).
1 5/32" seems to be the largest spline diameter, is that what you went with?
Were you going to make the splined shaft or were you going to get someone else to make one for you?

If anyone knows an engineering firm that can make custom splined shafts near Sydney (although that isn't critical) I'd appreciate any recommendations.

Cheers!
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gennyshovel
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Re: theTRUTH

Post by gennyshovel »

grumm441 wrote: Sun Jul 30, 2017 10:05 am I don't know if you noticed the VW powered bike in the pits. It had a low center of gravity and a long steering angle.
It also spent a lot of time lying on it's side.
G
It was also the 1st time the owner/rider had ever ridden a bike :shock:
Tiny DLRA# 484
Postiebike Racing , created & funded by TwoBob Engineering
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walkingpace
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Re: theTRUTH

Post by walkingpace »

I have a three plate 7 1/4" clutch. I bought it second hand without a flywheel then picked up a suitable flywheel separately from someone who had one sitting on a shelf for ages. Buying new is probably a far better option but I tend to collect parts slowly when they're cheap as my budget is limited. I'm adapting a 26 spline C4 input shaft to take the drive out of the clutch to the back wheel and the shaft for the other side I'm making myself. This hasn't been done yet but the plan is to cut and drill a disc to bolt up to the flywheel centre then weld this to a shaft. The whole lot will then be trued up on the lathe.

I've looked into getting splines cut but places that can do it are fairly limited and many aren't willing to take on a one off job. That would just be a matter of ringing around until someone says yes. The clutch splines are all designed for particular input shafts so the best bet is just to grab one of them and modify the other end of it. The rear of mine is quite narrow so there won't be an issue with the input shaft being too short either. If this was an issue on yours you could always move the clutch over to the right a bit.

The 7.25" clutches are very compact and unbelievably light which creates a lot of options for placement. As for shaft diameter and horsepower outputs they are designed for some pretty heavy use in powerful race cars with heaps of grip. When you translate that to driving a single wheel on a loose surface, pushing a motorcycle, I don't think you need to be too worried about putting in the biggest and toughest parts known to man. It isn't a dragster that will be instantly dumping all that torque through the driveline and hooking up. Rear tyre grip is going to be the weak link and you should be spinning up LOOOOONG before the shaft breaks. Might be easy for me to say seeing as how my motor does less than 300hp though...... :roll:
russelllowe
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Re: theTRUTH

Post by russelllowe »

Thanks Walkingpace, I spent some time chatting with a guy Brandon from Jegs yesterday ... he was really helpful. He didn't point me to any info online, but said the three disk clutches are good up to 1400hp or so; which should do aye! I think you're right re traction being the limiting factor. I'm thinking that with a excess of power it might be worth considering some aero downforce to help things out a bit.

The triple disk 7.25" v drive unit is $725 USD and a hydraulic throw out bearing (which looks pretty good too) is $234 USD ... so all up about $1250 of our peso's plus postage. Not bad considering other options go upwards of $4k (MTC and crowerglide for example) ... and your right, I don't need an aggressive take up, just a predictable take up at the start and firm hold once moving.

I'm still hopeful of running it with a once piece jack shaft ... which means a custom splined shaft. It turns out one of the technicians at work has some good fitting and turning experience so I'll chase him up.

Cheers!
grumm441
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Re: theTRUTH

Post by grumm441 »

gennyshovel wrote: Tue Aug 01, 2017 12:01 pm
It was also the 1st time the owner/rider had ever ridden a bike :shock:
I wasn't convinced that was the main issue
G
They make it
I make it work
russelllowe
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Re: theTRUTH

Post by russelllowe »

Hi Everyone,

Chopped the Suzuki yesterday ... for a 650 and tube frame there is a hell of a lot of gusseting and bracing around the headstock; makes it a good candidate for the Hoofhearted treatment. I'll use the swingarm too ... but most likely flipped upside down, driving the rear wheel on the right to give more room for the clutch/jackshaft.

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Harky; thought you might like the floor mockup.

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Cheers!
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walkingpace
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Re: theTRUTH

Post by walkingpace »

I've been giving some thought to your comments on a one piece jackshaft and I think you might be on the right track. My way of thinking is the splined shaft to match the spline on the clutch discs could run right through the centre of the whole unit and the section holding the flywheel could have a hollow centre with a couple of bearings in it and could spin around the other shaft. This would guarantee alignment and make it much easier to mount.

The only problem now is finding a 1-5/32" 26 spline shaft that's around 500mm long........

I wonder if maybe a diff shop would be capable of doing it. Surely cutting splines is part of their ordinary business. I'll make some inquiries and let you know if I turn anything up. I think we're both going to end up with effectively the same clutch arrangement in the end 8)
russelllowe
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Re: theTRUTH

Post by russelllowe »

Hi Walkingpace,

Looks like lunch time is a great time to check out whats happening online! Yes, that's what I had in mind. My only reservation being the distance between support bearings on the relatively small 1-5/32 shaft ... I'm thinking bending loads. Whats the distance between the back of the flywheel to the front of the clutch housing on the 3 disk setup? I might be over thinking that ... 500mm is not a long shaft. Jegs say my clutch has shipped, but would be nice to do some more planning before it arrives...

I think you're right re a diff shop. My guy here at work (the one with previous\engineering experience) got back to me this morning saying he was keen to help ... the soonest I can see him is next Thursday though. He says a place he used to work might be able to do the hardening if we cant do it here. I'll keep you posted too.

Strength in numbers (at least there will be some spare parts available when my bike proves to be unridable! ha!)

Cheers!
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