What did you do to or for or with your Laverda today?

Converted my custom Gates tooth-belt driven alternator on the SFQ to Gates Micro-V. A lot trickier than I anticipated with limited 'leg room' for pulley sizes, ratios and belt length. Dropped drive ratio from 1.75:1 to 1.6:1. The first incarnation used a narrower toothed belt, which broke after 6 months, so fitted a stronger, wider one. That lasted several years and many thousands of km but broke very soon after getting the Q on the road. The replacement lasted 800km before it stripped all its teeth (pic). How long would the second new one have lasted? Can't trust it. Possibly the wrong application for it here, but confused as to why the new ones don't seem to be coing when I had such a good run with the wider belt after I fitted it.

Gone for what I hope is a better alternative. It's possible the toothed belt doesn't like the high RPM I'm dishing out (but that's nothing new to my previous SF/C) or else Gates' quality control has dropped. Many hours toil on the little Emco lathe.

While I was at it, I drilled 'escape' holes into my second starter clutch - for removing stuck pins - and reconfigured my shift lever mech - shorter rod, closer to parallel angles and hopefully higher, so I can get my new boot under the lever without suffering a cramp! Phillip Island track day coming up and do NOT want to be thinking about how to shift down!
 

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Maybe a bit of slippage, eg no teeth might reduce shock loads. Just my guess. The first time I rode my modern Husky my new Alpine Star Tech 7s didn't fit under the gear lever as well, bit embarrassing having 20 blokes waiting for me to lift it one notch for a ride could start.
 
Andy said:
I trust we’re going to get some action shots from the Island PB!
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Hope so! Andy! Could have got some very nice action shots from the Jamieson ride a few weeks back. But I'd need a go-pro or someone wandering the 60km of tight, twisting country road with a camera.
 
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Vince said:
Now I am confused, Both pulleys don't have teeth on the new system.
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Gone from toothed belt pulleys on both drive and driven, to grooved pulleys on both. I replaced both - had to anyway to retain the 155mm spacing c-c. Definitely more 'give' in the latter, but obviously not the guaranteed non-slip. Gotta be some work being done when the alternator is spinning at 14,000rpm. Not sure what kind of load the alternator creates when lights are on. LEDs help.
 
piranha-bro2 said:
Gone from toothed belt pulleys on both drive and driven, to grooved pulleys on both. I replaced both - had to anyway to retain the 155mm spacing c-c. Definitely more 'give' in the latter, but obviously not the guaranteed non-slip. Gotta be some work being done when the alternator is spinning at 14,000rpm. Not sure what kind of load the alternator creates when lights are on. LEDs help.
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Kawasaki used grooved belt driven alternator and not toothed belt, it was introduced so they could disconnect it on production racer without removing it, keeping within the rules.
 
Exmoor beast said:
Kawasaki used grooved belt driven alternator and not toothed belt, it was introduced so they could disconnect it on production racer without removing it, keeping within the rules.
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Yes, I hve a GPZ750 alternator in the workshop and it has a fine-grooved pulley on it - the belts for them are very short and fram what I've read they tend to break and are bloody expensive. Mine is a much broader groove, designed as an 'auxiliary' belt for the auto industry. The ND alternator I converted came from an earlier GPZ1000 RX and it seemed to run from a transverse shaft across the back of the motor, then via a chain to a cross-pattern slot on the driven gear., complete with cush drives!
I'll probably remove my belt for the uncoming track day. If I can find a 240V outlet I'll bring a battery charger as insurance. although it's tempting to see how the new belt handles the constant high RPM.
 

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Blimey, giving me flashbacks from my old SF3 880 EFI 270 degree project! Used a Suzuki alternator with toothed belt. Centres worked out really well for the drive but preferred toothed belt as I had little scope for adjustment.
piranha-bro2 said:
Yes, I hve a GPZ750 alternator in the workshop and it has a fine-grooved pulley on it - the belts for them are very short and fram what I've read they tend to break and are bloody expensive. Mine is a much broader groove, designed as an 'auxiliary' belt for the auto industry. The ND alternator I converted came from an earlier GPZ1000 RX and it seemed to run from a transverse shaft across the back of the motor, then via a chain to a cross-pattern slot on the driven gear., complete with cush drives!
I'll probably remove my belt for the uncoming track day. If I can find a 240V outlet I'll bring a battery charger as insurance. although it's tempting to see how the new belt handles the constant high RPM.
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Yeah, the c-c spacing is the limiting factor. I don't need the EFI - although all the sensors and TPS would be very nice - my 880 270 motor runs 39mm Keihin FCRs and it absolutely flies.
 
piranha-bro2 said:
Yeah, the c-c spacing is the limiting factor. I don't need the EFI - although all the sensors and TPS would be very nice - my 880 270 motor runs 39mm Keihin FCRs and it absolutely flies.
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Took the EFI off when I sold it - was a bit of a complicated thing. My alternative setup was going to be a pair of Mikuni TRMs, I think 39’s, still got them somewhere and the ported big valve head. Sold it with standard head and carbs. Have a twin-port Beetle motor here waiting to be enlarged and squirted (or maybe Mikunied) when I get time…
 
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piranha-bro2 said:
Yes, I hve a GPZ750 alternator in the workshop and it has a fine-grooved pulley on it - the belts for them are very short and fram what I've read they tend to break and are bloody expensive. Mine is a much broader groove, designed as an 'auxiliary' belt for the auto industry. The ND alternator I converted came from an earlier GPZ1000 RX and it seemed to run from a transverse shaft across the back of the motor, then via a chain to a cross-pattern slot on the driven gear., complete with cush drives!
I'll probably remove my belt for the uncoming track day. If I can find a 240V outlet I'll bring a battery charger as insurance. although it's tempting to see how the new belt handles the constant high RPM.
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Quentin,

These alternators generally don't require sky-high revs to deliver decent wattage and they don't give you something for nothing either, ie, your power input is always higher than what you're recieving... I can't figure out the stock drive ratios from the csm.nl diagrams, but your drive ratio seems a tad excessive to me. Surely they don't spin at crank revs on the Kwakker? Maybe you can find a pony or 2 and extend belt life by running the alternator a bit slower.

piet
 
That's what I would have thought too Piet, but when I first fitted it auto elec with a lot of experience putting them into ultralites said they definitely like to spin - and I'm pretty sure they do run at eq crank speed in the Jap fours. The GPX750 one in the garage has a very small finely grooved pulley on it and they must spin to around 12k. But you're right and I do feel better with it running 1.6:1. Currently running a 495mm belt - I'll check out what the next size up is.

I can always experiment, and machining the pulley on the alternator is WAY easier than the one that sits over the starter clutch. So if I went for the next belt size up and enlarge the driven pulley to suit I might be able to save a bit of grief and gain even more HP - not that the Q needs it ... it is very bloody quick.
 
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Visited Dave Fitz's emporium yesterday to talk about 500 race bikes and drop off a gear cluster I acquired from Belgium about 3-4 years ago that came from a F500. We compared it with a standard gearbox cluster and 1st and 2nd gears were noticeably different as was the 6th gear.
The parts list suggests the F500 had different 1st, 2nd and 3rd gear differences, so perhaps a previous owner decided to make further changes.
Whatever, Fitz is planning to see if he can get the gears replicated at a hopefully affordable price.
I also took a box of other gear clusters I had collected from a couple of different sources that I hadn't really studied previously. Most looked standard, but one looked different again to the std and F500 version of the 500 gearbox. Perhaps it's from a 350 or even an Atlas as I suspect they might be different again. I need to dig deeper.
 
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