Front 3.60 vs 4.10?

Status
Not open for further replies.
Leonc

Leonc

Joined
Feb 10, 2018
Messages
79
Country flag
On my Mk111, I have a Pirelli Sport Demon 100/90 x 19 tyre on the front. All mounted on a WM2 or 1.85 rim. It came with the bike and is near its end of life.
This bike has never been as sharp with turning at low or high speed, and sometimes feels darn clumsy, when compared to my previous Commando's.
My 650SS has a 3.60 and my A75 has a 4.10 front, and they are much nimbler at all other speeds.
I have searched through all the threads and comment's, with out specific result. Has anybody has a personal experience of changing from a modern tyre, such as the above, to a TT100 of either possible size?
If so what was your experience?
Thanks for any responses.
 
My mk3 came on 3.60 TT100s. Tread was good, but they were nearly 10yrs old. After 100 or so miles I replaced them with 4.10 TT100s. I'm happy with them, for spirited road rides, but I noticed the 4.10s feeling slower turning / heavier than the 3.60s.
 
Don't know about the A75, but I don't think the Commando will ever feel as light into the corners as a 650ss. It just takes a wee bit more effort to do the same thing on a Commando.
The rubber bike is never going to be quite on par with the Featherbed.
Small price for the great reduction in vibration.

Glen
 
I used to run 100/90 Roadriders front and back, but tried a 90/90 on the front i wouldn't go back. Definitely sharpened up the steering.
Last change was back to TT100's. At my speeds i cant say that tyre manufacturer or model makes a noticeable difference.
 
An Avon Roadrider Mk2 (100/90) up front feels good to me - but might have to try 90/90 after @ntst8 's comment.
Could you elaborate on what was different?

Here's the Avon data on the two:
Front 3.60 vs 4.10?
 
Last edited:
I think the 3.60 is good for something like a P. R. Maybe , but put a lot of load on it , cranked over , braking , It'll wash out , more than a 4.10 .

Better solution is go to T C's 5.000 16 rear . TOURING , or late P R set up 4.10 19 F 4.25 18 R .
Tho a 4.00 19 K 70 on the rear , if youre not a ' Scrape the Pegs ' man isnt to bad .
Id done 8 miles in 6 minutes on one , in torential rain where you couldnt see the speedo .
23 teeth gave 112 in third , only in top on the straights . they seemed mighty uneven !
The last two miles was at the posted limit . Whatever the figures were , the Avg. was 90 . oops .

If youre into ' adventure riding ' the 4.00 K 70 would be good . think I had a 3.60 Road Runner front .
You Would Not try'n drag the pipes , with this set up . If you must , the 4.10 F 5.00 16 R would work .

Front 3.60 vs 4.10?
these were actually ' The Choice ' for a grooved hard track Flat Track Tyre , back in the 60s - 70s till Good Year got their act together .

Looked like these , which are , apparrently , Dunlop DT3 R tyres .
Front 3.60 vs 4.10?
 
Last edited:
Eres the 19 & 18 Combo , Quicker .

Front 3.60 vs 4.10?
Front 3.60 vs 4.10?


The Wider Shoulders Keep the machine from scrapeing so much . If thats a problem .

Nuver Fred , https://www.accessnorton.com/NortonCommando/tires-for-my-69-commando.13871/page-2 or two https://www.accessnorton.com/NortonCommando/type-rims-and-tires.24034/page-2

Theres Pictures around of T C & his favoured 16 rear for his Commando road bikes , if you can find them . Most tyres were 26 in tall . But the 4.00 - 19 k-70's not !
Youve gotta check the mudguard bolts Go OUTWARD . Maybe Thinned Heads or Nuts . Loctited . dome Head ? or they can grove the tyre if the roads rough .
Ran Gas Girlings with 110 Lb springs . good . seldom Bottomed. Never Solo .
 
These Perillies were the SOFT TRACK / Cushion choice . unsuitable for tarmac . DRIFT it you utilise throttle or brake , past 1/4 .

Front 3.60 vs 4.10?


The K 70s , below. Arnt To Bad . good Feedback & altering line . dont mind aggressive riders on tarmac , if theyve got more than half a brain .

Front 3.60 vs 4.10?


Good Traction on any unsealed going . the 4.00 - 19 is a big tall tyre . Guard might foul , front ! . The Roadrunners fine front in combo .

the Current issue are likely ' superior ' to the 70's ones !? .
 
Matt Spencer said:
These Perillies were the SOFT TRACK / Cushion choice . unsuitable for tarmac . DRIFT it you utilise throttle or brake , past 1/4 .

Front 3.60 vs 4.10?


The K 70s , below. Arnt To Bad . good Feedback & altering line . dont mind aggressive riders on tarmac , if theyve got more than half a brain .

Front 3.60 vs 4.10?


Good Traction on any unsealed going . the 4.00 - 19 is a big tall tyre . Guard might foul , front ! . The Roadrunners fine front in combo .

the Current issue are likely ' superior ' to the 70's ones !? .
Click to expand...
Matt - I realise you want to post more of your impressive collection of archive photos/magazine articles, but please explain how that post is remotely helpful here?
 
Leonc said:
On my Mk111, I have a Pirelli Sport Demon 100/90 x 19 tyre on the front. All mounted on a WM2 or 1.85 rim. It came with the bike and is near its end of life.
This bike has never been as sharp with turning at low or high speed, and sometimes feels darn clumsy, when compared to my previous Commando's.
My 650SS has a 3.60 and my A75 has a 4.10 front, and they are much nimbler at all other speeds.
I have searched through all the threads and comment's, with out specific result. Has anybody has a personal experience of changing from a modern tyre, such as the above, to a TT100 of either possible size?
If so what was your experience?
Thanks for any responses.
Click to expand...
Do Pirelli specify a rim width for that tyre?
I would be surprised if a 1.85 rim was wide enough?

My point being that IF the rim width advice has not been followed, the tyre characteristics could change, so if the 100 tyre was not working as intended, it’s not really a discussion about a 100 vs a 90 etc.

FWIW I run a 100/90 19 Roadrider on mine with the specified rim width and am very happy with the handling on road and track.
 
This is slightly off-topic, but I now have Counteract beads in both tyres and no balance weights.
No change at all - remains well balanced. The bonus is that it will adapt to tyre wear and retain balance for the life if the tyre.
Costs about $2.50AUD per tyre.
I would thoroughly recommend them - their competition (Dynabeads) are probably just as good.
Cheers

PS: I have tubes, but apparently they work well on tubeless,
 
Matt Spencer said:
I think the 3.60 is good for something like a P. R. Maybe , but put a lot of load on it , cranked over , braking , It'll wash out , more than a 4.10 .
Click to expand...
What bullshit! But, at least it's different bullshit, elsewhere recently we had the 'insight' that a 90/90 is marginal under braking!

I raced with a 3.60 front, and currently with a 90/90 front on two different bikes, of different weights.

It won't 'wash out' in road use, and hasn't in my experience in race use.

The tyre is a better size for a wm2 rim and will steer quicker compared to the larger tyre.

Fitting 4.10s front and rear has been noted simply as a cost saving measure by Norton, buying all tyres in one size versus 50/50 two sizes.

Some people like it, and in period used it effectively in production racing, some don't.

Regarding your pictures of Thruxton Motorcycles' Tony Holland, they were one of the first to adopt the KR91 endurance rear tyre, wider than a 4.10 (4.50 I think) and in 18" size it was the same rolling diameter as a 19" 4.10.
 
Last edited:
robs ss said:
This is slightly off-topic, but I now have Counteract beads in both tyres and no balance weights.
No change at all - remains well balanced. The bonus is that it will adapt to tyre wear and retain balance for the life if the tyre.
Costs about $2.50AUD per tyre.
I would thoroughly recommend them - their competition (Dynabeads) are probably just as good.
Cheers

PS: I have tubes, but apparently they work well on tubeless,
Click to expand...
Probably is off topic, but I have been using dynabeads for years in my race bikes.

Actually they are good for the life of the tube where used.....which in my case has been 3 or 4 tyres.

I will look out for Counteract, looks a lot cheaper.
 
Fast Eddie said:
Do Pirelli specify a rim width for that tyre?
I would be surprised if a 1.85 rim was wide enough?

My point being that IF the rim width advice has not been followed, the tyre characteristics could change, so if the 100 tyre was not working as intended, it’s not really a discussion about a 100 vs a 90 etc.

FWIW I run a 100/90 19 Roadrider on mine with the specified rim width and am very happy with the handling on road and track.
Click to expand...
I doubt that it has ever been right as it was the previous owners choice. So far it is sounding like 3.60 or 90/90 is the way to go with my rim.
 
Perilli ? well . . . ,. if someone saw the $ 20 Perrili's , and was somewhat tempted . They Might THINK TWICE ,
Theyre actually hilerious to ride on , but if tarmacs involved , frorget it .

3.60 Vs 4.10 .

Well , RACING , you tend to be ' On It ' , If its the Classic ' Run the Bends ' fine .

The ' Trigonics ' though , tend to be tip toey , and follow seams etc in the tarmac , and cambers to a degree . Depending on the cycle . ( The Home Built Triton was good ) the 3.00 KR 76 empacises this .
However ,
If youre a ' Run it into the bends on the front ' , ' pushing ' the largers a better bet . The C'do with 3.00 KR 76 F & 4.1 K 81 R , no idle - Theres a r h off camber with a kink left to Sq on the downhill main road .
Holding a tad of throttle & some brake , in the wet the Front & Back would push . Due to the right lock for the off camber .
Another off camber Rt always seemed slow , trying not to be , it'd always drift ( slightly back out - but cranked over always both ends would be drifting . NOT one end slideing . So Triton Frame was designed to
do Both . If you brought the throttle up , in a drift - it'd transition to a slide . A bit safer . More Control .)

So , the idea is to get a Commando to do likewise , without flapping all over the place . Even if the road is a bit uneven . ALL the Highways were CHIP SEAL GRANIT CHIP . And after a year UNEVEN .
A freshly reealed road was usually past round as ' worth a ride ' , even if far off .

A ' Racing Posture & Clambering around the plot , arnt quite the same as wedged in two up with luggage . Thus ' Riding Style ' and tyre choice are interelated . High mile touring Id go for big rubber &
TRACTION .
Sharp Steering gets wearying on other than first class surfaces . So local roads'd be relevat too .
AND see the preservatives scrrubbed off . A 1400 Kwacker ended up on its side on the turn onto the road on new tyres . Temp. zero . A grand or two of trinklets down the drain .

If you were stropping it, solo . The Narrow front is precise . But Downhill pushing the frontthrough the turn entry ( to apex ) as some are want , wont on a widdle fing . Itll tend to wobble .
Unless you throttle it & dfrift in . Which might be somewhat unlikely on the road . There being old pilots & bold pilots , but no ol;d bold pilots . Tho theres a few full of metal from ' the Track '
if theyve been caught out .

So , Generally , TRACTION is KING , for on the ROAD . And I should think the front should stay adhered in the not so unlikely event of a emergency brake and steering input . Perhaps past the limit .
Like your fine tne race chassis balance . But with semis , dogs , here wombats and roo's on the course . NZ the only mobile chicanes are man made . So the skys the limit . Aus theres Roo's so limits sane .
 
Matt Spencer said:
Perilli ? well . . . ,. if someone saw the $ 20 Perrili's , and was somewhat tempted . They Might THINK TWICE ,
Theyre actually hilerious to ride on , but if tarmacs involved , frorget it .

3.60 Vs 4.10 .

Well , RACING , you tend to be ' On It ' , If its the Classic ' Run the Bends ' fine .

The ' Trigonics ' though , tend to be tip toey , and follow seams etc in the tarmac , and cambers to a degree . Depending on the cycle . ( The Home Built Triton was good ) the 3.00 KR 76 empacises this .
However ,
If youre a ' Run it into the bends on the front ' , ' pushing ' the largers a better bet . The C'do with 3.00 KR 76 F & 4.1 K 81 R , no idle - Theres a r h off camber with a kink left to Sq on the downhill main road .
Holding a tad of throttle & some brake , in the wet the Front & Back would push . Due to the right lock for the off camber .
Another off camber Rt always seemed slow , trying not to be , it'd always drift ( slightly back out - but cranked over always both ends would be drifting . NOT one end slideing . So Triton Frame was designed to
do Both . If you brought the throttle up , in a drift - it'd transition to a slide . A bit safer . More Control .)

So , the idea is to get a Commando to do likewise , without flapping all over the place . Even if the road is a bit uneven . ALL the Highways were CHIP SEAL GRANIT CHIP . And after a year UNEVEN .
A freshly reealed road was usually past round as ' worth a ride ' , even if far off .

A ' Racing Posture & Clambering around the plot , arnt quite the same as wedged in two up with luggage . Thus ' Riding Style ' and tyre choice are interelated . High mile touring Id go for big rubber &
TRACTION .
Sharp Steering gets wearying on other than first class surfaces . So local roads'd be relevat too .
AND see the preservatives scrrubbed off . A 1400 Kwacker ended up on its side on the turn onto the road on new tyres . Temp. zero . A grand or two of trinklets down the drain .

If you were stropping it, solo . The Narrow front is precise . But Downhill pushing the frontthrough the turn entry ( to apex ) as some are want , wont on a widdle fing . Itll tend to wobble .
Unless you throttle it & dfrift in . Which might be somewhat unlikely on the road . There being old pilots & bold pilots , but no ol;d bold pilots . Tho theres a few full of metal from ' the Track '
if theyve been caught out .

So , Generally , TRACTION is KING , for on the ROAD . And I should think the front should stay adhered in the not so unlikely event of a emergency brake and steering input . Perhaps past the limit .
Like your fine tne race chassis balance . But with semis , dogs , here wombats and roo's on the course . NZ the only mobile chicanes are man made . So the skys the limit . Aus theres Roo's so limits sane .
Click to expand...
Can you summarise that Matt - couldn't get your drift (pardon the pun)?
 
Status
Not open for further replies.
Back
Top