Tyre choice advice

Well, actually after my first ride on my SF last Sunday I’ve decided it really needs rearsets, the pegs are like 6ā€too forward for me, if I can’t find what I need I’ll have to make some.
Make sure your tyre is rated for the max speed of your bike.

This tyre was on Jack Frost's turbo Hayabusa when it came apart at over 200mph on Pendine Sands (UK) a couple of weeks ago. Amazingly he stayed on the bike and came to a stop running on rim of carbon wheel. He was apparently uninjured, but looking at the damage to the back end of the bike, I reckon he got a nasty slap in the arse from the busted tyre.
good advice indeed, going with H rated (as fitted), that guy Jack Frost was lucky to get away so lightly, the rear subframe is well smashed up!
Pendine isn’t far from me,years back I worked on a film there (I’m a key grip) called ā€˜overland’, about LSR attempts in the 1920’s, i had to mount film cameras all over ā€˜BABS’ the 27 litre aero engined car built by Parry Thomas. He was the first driver killed attempting to set a new LSR, in March 1927 iirc. It was magnificent to see and hear that behemoth run on the beach. One of my best days at work ever!
 
Wow, what an incredible film to work on! I'll have to look out for it - 27 litre aero engine!!! Faaark!

Totally agree about rearsets - std SF ergonomics os for chimps I reckon. You don't have to go radical to get a vast improvement. When I was a poor young man (not I'm a poor old man!! :cool:) I managed to retain the std SF1 pegs and rotate them back on their splines then rig up a bracket off the swingarm axle that the gear lever could pivot from, then a simple linkage. I cutand inch or a bit more off the brake pedal and had the foot plate rewelded on without even discolouring the chrome. It kept things fairly stock (only the shorter brake pedal was permanent change).

Much better solution is to do it 'properly' but that might mean more mods - if you know how many rivets are on your bike then that won't appeal ;-)
The kits that insert into the triangle like Jota rearsets seem popular. I made my own alloy plates, tossed the rear drum for a spoked disc and custom made the hole gear brake system from triple and Jota levers with a Kwaka master cyl. That one's a keeper.
 
going with H rated (as fitted), that guy Jack Frost was lucky to get away so lightly, the rear subframe is well smashed up!
Blimey, I didn't know his tyre was only H rated. That's rated to a max of 130mph (210kph). I wouldn't use an H tyre on a road bike!
I think his best run was close to 260mph (420kph), so he was doing twice the rated speed of the tyre. I guess it shows that there's a pretty good safety margin in tyre speed ratings.
Maybe he'd have been OK with a V rated tyre (149mph).
 
Starman didn't mean that the Jack Frost bike had a H-rated tyre did he? I thought he was referring to his own bike.
Hi all
yes, I was referring to my bike tyres, but, reading my post, I can see now my poor sentence construction, apologies Dellortoman!
Doh! English language is not a subject to which I claim mastery, probably in part to my miss-spent youth…
in school I used to bunk off lessons I hated and spend the time in the metalwork shop. The craft teachers would turn a blind eye to such shenanigans, but eventually I was caught out and punished harshly. But they let me keep the go-kart I was making.
Having walked many miles of Pendine sands when I was filming there, I can attest that there was more than simply sand, I noticed sharp seashell pieces, stuff that floated in and left by the tide, also, I found an unrecognisable piece of rusty iron fixed to a remnant of wood, it may have once been part of a boat?
It is concievable that his (jack frost’s) machine may have run over such an object, causing minute tyre damage which at such a speed escalated to catastrophic failure?
i know it is customary for a crew to walk the timed course to look out for any such ā€˜foreign objects’ the process called, iirc, ā€˜foding’, but if something was just below the surface, invisible…
 
I need a new rear tyre, the Bridgestone T30 is now T31. I need to write down a date and milage for this, I seem to be blowing through tyres really quickly these days, no idea how with lockdown and the pandemic. Typically it's the middle that's warn, and these are dual compound to boot. As usual, I am thinking just one more ride, but it gets risky if you get rain on that day.
 
Vince I use a spreadsheet to keep fuel economy details for each of my vehicles, and keep notes on services and tyre changes as well.

cheers

bazzee
 
I rely on the Guilt method, when my stomach starts to get butterflies about how long since the bike got an oil change then I do it. It usually works out way sooner than factory recommendations. My Catholic guilt has at least one plus. I will start marking my calendar on the tyre front. It seems recent but it might be pre-Tassie which was thousands of ks ago.
 
I need a new rear tyre, the Bridgestone T30 is now T31. I need to write down a date and milage for this, I seem to be blowing through tyres really quickly these days, no idea how with lockdown and the pandemic. Typically it's the middle that's warn, and these are dual compound to boot. As usual, I am thinking just one more ride, but it gets risky if you get rain on that day.
Perhaps you are riding on different roads through these times. Some types of road surface are far more abrasive than others, especially in Australia where the norm out in the country is bitumen seal, where they spray wet molten tar and pour a layer of specified size gravel/stones over it to stick into the tar, as compared to hot mix type surface.
Starman, your english grammar is good. Not only do you know how to spell tyre, but you don't use apostrophes on plurals.
It is fairly straightforward to jig up some rear sets for your SF, I seem to recall that the Tarozzi ones are available to buy and fit. Both my SF2 are converted to rear disc, as it seems that getting a neat and effective setup for the rear drum brake can be a challenge. For both of mine I have used triangle plates held in place with small welded on steel brackets that could be easily removed if so desired, and used modified pegs and levers from SF3 that were available at the time when they were available as they had pivots and stuff meant for crossover linkages.
It must have been great experience getting up close to those LSR attempts.
 
maybe it was more likely to go in a straight line with the rim on the ground than with the fitted tyre on sand, sand forchisakes, I dont like the feel of a trail bike on the beach hard/wet sand at 40MPH, never mind 200MPH
CLEM
 
Perhaps you are riding on different roads through these times. Some types of road surface are far more abrasive than others, especially in Australia where the norm out in the country is bitumen seal, where they spray wet molten tar and pour a layer of specified size gravel/stones over it to stick into the tar, as compared to hot mix type surface.
Starman, your english grammar is good. Not only do you know how to spell tyre, but you don't use apostrophes on plurals.
It is fairly straightforward to jig up some rear sets for your SF, I seem to recall that the Tarozzi ones are available to buy and fit. Both my SF2 are converted to rear disc, as it seems that getting a neat and effective setup for the rear drum brake can be a challenge. For both of mine I have used triangle plates held in place with small welded on steel brackets that could be easily removed if so desired, and used modified pegs and levers from SF3 that were available at the time when they were available as they had pivots and stuff meant for crossover linkages.
It must have been great experience getting up close to those LSR attempts.
Thank you, you are too kind!
regarding rearsets for my SF, I am going the triangular alloy insert path, (clamped in place by contoured alloy blocks behind, that mirror the tube profile)
I just found and purchased some tarozzi folding foot pegs, with matching levers, and I have some nice bits of 8mm and 10mm alloy plate in my workshop stockpile.
i am keeping the rear drum brake, (front is a drum also, the first laverda type) as i am quite happy with them, they are the best drum brakes I’ve ever had on a motorcycle. The twin SLS front drum on my ā€˜74 Ducati desmo single was my previous benchmark of excelence, but due on no part to the little 250’s light weight.
I rode it to the Isle of Man in 1978 with my then best buddy (now brother in law!). He was riding his triumph Tiger 100, both of us side by side flat out down to Creg-ny-Bar, both pretending we were Mike Hailwood…I could easily outbrake him, he said there was daylight under my rear tyre as I sailed past.
i need a short lever to fit the gear change splined shaft , like I’ve seen fitted to an SFC in photographs. If anyone has one to sell??
I have some nice stainless bar 10mm dia to make the connecting rod, and two M6 spherical rod end joints. For the rear brake cable, I will either turn up steel cable end stop on my lathe and weld it to the frame, or I may machine up an alloy block that will clamp to the frame tube near the bottom R/H corner of the side panel To act as the cable outer end stop.
Im studying as many photographs as I can find to see how others have done it.

Btw, i still have that 250, but I was a mad 21 yr old and weighed just 125lbs then!

I’m curious, can anyone tell me, is the later type laverda drum even better than my earlier laverda drum? Or similar?
how do they compare?
If anyone has any sage advice for me, as, although I have other 70’s Italian classics, my SF is my first Laverda, so I am all ears and grateful for any hard earned wisdom.
thanks for any input,
martyn.
 
Most people find a broken gear pedal to fashion a stubby lever to connect to. It sounds like you are well on the way with the job, it will make the bike so much more comfortable.
Piet has posted about how to get the best out of Laverda drums, a search should find the info.
Yes, those two sided single leaders on Duc single were as good a drum as I have ever used, I have had a couple of 450s and never had a problem with them. The Lav brake is far more complicated and has a lot more weight to work on - and they don't work to stop you rolling backwards iirc.
 
Thank you, you are too kind!
regarding rearsets for my SF, I am going the triangular alloy insert path, (clamped in place by contoured alloy blocks behind, that mirror the tube profile)
I just found and purchased some tarozzi folding foot pegs, with matching levers, and I have some nice bits of 8mm and 10mm alloy plate in my workshop stockpile.
i am keeping the rear drum brake, (front is a drum also, the first laverda type) as i am quite happy with them, they are the best drum brakes I’ve ever had on a motorcycle. The twin SLS front drum on my ā€˜74 Ducati desmo single was my previous benchmark of excelence, but due on no part to the little 250’s light weight.
I rode it to the Isle of Man in 1978 with my then best buddy (now brother in law!). He was riding his triumph Tiger 100, both of us side by side flat out down to Creg-ny-Bar, both pretending we were Mike Hailwood…I could easily outbrake him, he said there was daylight under my rear tyre as I sailed past.
i need a short lever to fit the gear change splined shaft , like I’ve seen fitted to an SFC in photographs. If anyone has one to sell??
I have some nice stainless bar 10mm dia to make the connecting rod, and two M6 spherical rod end joints. For the rear brake cable, I will either turn up steel cable end stop on my lathe and weld it to the frame, or I may machine up an alloy block that will clamp to the frame tube near the bottom R/H corner of the side panel To act as the cable outer end stop.
Im studying as many photographs as I can find to see how others have done it.

Btw, i still have that 250, but I was a mad 21 yr old and weighed just 125lbs then!

I’m curious, can anyone tell me, is the later type laverda drum even better than my earlier laverda drum? Or similar?
how do they compare?
If anyone has any sage advice for me, as, although I have other 70’s Italian classics, my SF is my first Laverda, so I am all ears and grateful for any hard earned wisdom.
thanks for any input,
martyn.
Hi Martyn,
A while back when ordering some parts from Wolfgang and talking about my Sf, he made the comment that he preferred the first version as the cams are being pulled together equally at the same time. I've only had a 30 odd mile run home on mine from buying it, but was impressed at how smooth the brake was.
 
I've ridden on both. One was my SF1 (later type) and I had to get rid of it before I killed myself. I ended up off the road in the Adelaide Hills thanks to that brake. Maybe it wasn't set up perfectly, but I needed something that didn't require that much attention when I was young and poor. I always centred the backing plate when refitting the wheel, which always helped a lot. Replaced it with a Yamaha TZ 4LS and used that for many years - brilliant, but too fragile - went through two of them. With discs available and virtually trouble free it was a no-brainer to upgrade.

Rebuilt an SF a few years back that had the early type like yours - it had great bite on initial application but when you wanted more the lever came in but the rate of deceleration didn't change. Had to take evasive action to avoid running into the back of a turning vehicle (the car I was behind saw it late and flipped lanes very suddenly, leaving me exposed). Discs would have pulled me up without problem. Of course all this depends on how hard you want to ride/brake. My take is that if the brake can't lock the front wheel it isn't up to the task. Just my opinion and many will disagree.
 
Crashed my SF0 3 times on the original drum, it behaved just as Q describes, good initial bite then nothing, go for a overtake, think twice about it, pull on the anchors, nothing, hmmmm, think I'll crash over there.......
 
Had a bit of a miscommunication when ordering my new tyre, for some odd reason they heard and tried ordering a Bridgestone T37. And hit a wall with that. The latest type is now a T32, apparently wth better than before wet grip. I had no complaints before including that nightmare Tassie trip with its Polar Vortex with Snow and rain and big winds, the front brake didn't like it but the tyre was fine. Its a week to arrive from its border crossing Queensland BTW you need at least a 3inch rear rim to run these tyres on the rear
 
Had a bit of a miscommunication when ordering my new tyre, for some odd reason they heard and tried ordering a Bridgestone T37. And hit a wall with that. The latest type is now a T32, apparently wth better than before wet grip. I had no complaints before including that nightmare Tassie trip with its Polar Vortex with Snow and rain and big winds, the front brake didn't like it but the tyre was fine. Its a week to arrive from its border crossing Queensland BTW you need at least a 3inch rear rim to run these tyres on the rear
Whatcha stump up for Vince.... 140 or 160 rear ?
 
A little more I think, they let me slide on payment till it arrives. I Will let you know. It's a bike shop I have used for 30 years, a couple of years back it was sold to a new bloke. The original arrangement was to order the tyre, pull the wheel at home and drop it off, next day you just paid and picked up the wheel with the new tyre fitted. It's a bit confusing now as Marty works there as a Mechanic and somehow they just assumed he would fit the tyre to the wheel in his lunch time for free. And I had no idea that was happening. I had to make it clear that I didn't expect anyone, the shop or Marty to not get paid at the correct long-term cost for their time. So for the last 2 tyres fitting was free, we will see this time. BTW I love Marty doing this, he knows his Borrani shit.
 
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