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K75 Spitfire vs. Battlax tires

98lee said:
The recommendation is more related to replacing what came standard on the bikes both in speed rating and in load capability. Same with their car recommendations. The S came with the Metzler Laser (before that was replaced with the Lasertec). I believe the other K75s came with the Metronic (a lower performance, higher milage tire).

The recommendations do not list every upgrade possible, just the minimum replacement. Going with higher performance tires is at the choice of the owner.

Yeah I've burned up ALOT of Lasertecs until I finally got curious about the good things that I'd heard about the BT45s on this forum. I'm on my third set of BT45s and am very pleased. A noticeable improvement.



:dance:dance:dance
Click to expand...

Lee, that perfectly answered the question. I didn't understand the minimum standard tire replacement for the fitment listing. Bridestone could not have answered it better (if they weren't too busy to read and reply to my email queries :violin).

I'll probably replace my BT45 rear tire with the same, and change my S11 front tire to the BT as well.

Thanks much,
88 K75 Tired, but loyal.
pete
 
98lee said:
Bridgestone makes BT45s in H-rated and V-rated, but they only make the correct rear sizes in V-rated. You did not say which model K75 you have, so I am assuming that it is not an S.

The sizes you want if you have an 18" rear tire are: Front: 100/90V-18, Rear 130/80V-18. If you have an S you want 130/90V-17 for the rear.

http://www.motorcycle-superstore.co...-Battlax-BT-45V-Sport-Touring-Front-Tire.aspx

http://www.motorcycle-superstore.co...ne-Battlax-BT45V-Sport-Touring-Rear-Tire.aspx




:dance:dance:dance
Click to expand...


Hi,
My ride is a K75 standard. I currently have a BT-45R 120/90-18 rear tire. You think the 130/90-18 aspect ratio is better?

pete
 
petegiar said:
Hi,
My ride is a K75 standard. I currently have a BT-45R 120/90-18 rear tire. You think the 130/90-18 aspect ratio is better?

pete
Click to expand...

I don't know for a fact, as all my experience has been with Ss and 17"rear tires, but I do know the bike will handle a 130 cross section tire (that is what comes stock on all Ss and K100s) and the rim width (2.75" same as an S) is right for a 130 cross section. Going from a 120/90 to a 130/80 should keep the diameter very close (about 3/8" shorter). It would give you about 3/8" wider tread. It would give you the same width and diameter as an S. Unless someone has a good reason NOT to go that way, I would go for the wider tire as it is a standard +1 upgrade. I truly believe it would be the best way to go.




Home > Products > ON ROAD > BT-45V / BT-45



• Infomation for Safety Use of MC tires
• MC Tire Designations



In fields of tire size, index of "TT" and "TL" shows as follows.
TT : Tube Type
TL : Tubless type



BATTLAX BT-45 is a touring type tire offered in both H and V rated speed symbols. BATTLAX BT-45 gives all-round street performance, with the emphasis on riding comfort, long mileage, wet performance, all designed by the latest tire developing technologies of Bridgestone. With the comprehensive tire sizes, BATTLAX BT-45 replace BATTLAX BT-35 and BT-17V.


Front
Rear

Technical Features

BT-45V
[Compound, pattern and shape]
•Same high performance as the BT-45.

[Construction]
•Incorporates Sports Sact (rear tire). Provides the same high level performance as the BT-45, but the extra potential of the V range specifications tolerates an even higher speed range.

BT-45
[Compound]
•Battlax BT-45 rear contains Dual Tread Compound (DTC). The center compound secures long mileage and durability, while the tread edge compound secures grip and traction in corners. Also, Battlax BT-45 compound contains Silica for additional wet performance.

[Pattern]
•The newly developed zigzag center grooves promise high speed stability. The smaller, directional grooves in front tire effectively remove water for wet performance.

[Profile]
•Designed with CTDM, the unique sidewall profiles of Battlax BT-45 give high speed stability and riding comfort by cushion effect The large crown radius also contributes to the stability in high speed touring.


BT-45V Front

Tire Size Rec. Rim Rim Width OD TW
(inch) (inch) (mm) (mm)
110/90-16 M/C 59V TL 2.50 2.15 - 3.00 604 111
120/80-16 M/C 60V TL 2.75 2.15 - 3.00 598 121
110/80-17 M/C 57V TL 2.50 2.15 - 3.00 608 107
100/90-18 M/C 56V TL 2.50 1.85 - 2.75 637 100
110/80-18 M/C 58V TL 2.50 2.15 - 3.00 633 107
110/90-18 M/C 61V TL 2.50 2.15 - 3.00 655 111
100/90-19 M/C 57V TL 2.50 1.85 - 2.75 663 100

BT-45V Rear

130/90-16 M/C 67V TL 3.00 2.50 - 3.50 634 138
150/80-16 M/C 71V TL 3.50 3.00 - 4.00 646 154
120/90-17 M/C 64V TL 2.75 2.15 - 3.00 642 121
130/90-17 M/C 68V TL 3.00 2.50 - 3.50 664 135
140/80-17 M/C 69V TL 3.50 2.75 - 3.50 656 143
150/70-17 M/C 69V TL 4.00 3.50 - 4.50 641 149
120/90-18 M/C 65V TL 2.75 2.15 - 3.00 673 121
130/80-18 M/C 66V TL 3.00 2.50 - 3.50 663 131
140/70-18 M/C 67V TL 4.00 3.50 - 4.50 652 145
140/80-18 M/C 70V TL 3.50 2.50 - 3.50 681 143
150/70-18 M/C 70V TL 4.00 3.50 - 4.50 670 150



BT-45 Front

100/90-16 M/C 54H TL 2.50 2.15 - 2.75 586 100
100/80-17 M/C 52H TL 2.50 1.85 - 2.75 595 100
110/70-17 M/C 54H TL 3.00 2.75 - 3.50 589 106
110/80-17 M/C 57H TL 2.50 2.15 - 3.00 608 107
120/70-17 M/C 58H TL 3.50 3.00 - 3.50 605 123
90/90-18 M/C 51H TL 2.15 1.85 - 2.50 619 89
100/80-18 M/C 53H TL 2.50 1.85 - 2.75 617 100
100/90-18 M/C 56H TL 2.50 1.85 - 2.75 637 100
100/90-19 M/C 57H TT 2.50 1.85 - 2.75 663 100
90/90-21 M/C 54H TT 2.15 1.85 - 2.50 702 92
90/90-21 M/C 54H TL 2.15 1.85 - 2.50 702 92

BT-45 Rear

130/90-16 M/C 67H TL 3.00 2.50 - 3.50 636 132
110/90-17 M/C 60H TL 2.50 2.15 - 3.00 630 110
120/80-17 M/C 61H TL 2.75 2.15 - 3.00 624 121
130/70-17 M/C 62H TL 3.50 3.00 - 4.00 617 136
130/80-17 M/C 65H TT 3.00 2.50 - 3.50 638 131
130/80-17 M/C 65H TL 3.00 2.50 - 3.50 638 131
140/70-17 M/C 66H TL 4.00 3.50 - 4.50 627 145
150/70-17 M/C 69H TL 4.00 3.50 - 4.50 641 149
110/80-18 M/C 58H TL 2.50 2.15 - 3.00 633 110
110/90-18 M/C 61H TL 2.50 2.15 - 3.00 655 110
120/80-18 M/C 62H TL 2.75 2.15 - 3.00 654 120
130/70-18 M/C 63H TL 3.50 3.00 - 4.00 637 128
140/70-18 M/C 67H TL 4.00 3.50 - 4.50 652 145
150/70-18 M/C 70H TL 4.00 3.50 - 4.50 668 149

Please consult your local Bridgestone representatives for product availaility and legal conformity.





:dance:dance:dance
 
Last edited:
98lee said:
I don't know for a fact, as all my experience has been with Ss and 17"rear tires, but I do know the bike will handle a 130 cross section tire (that is what comes stock on all Ss and K100s) and the rim width (2.75" same as an S) is right for a 130 cross section. Going from a 120/90 to a 130/80 should keep the diameter very close (about 3/8" shorter). It would give you about 3/8" wider tread. It would give you the same width and diameter as an S. Unless someone has a good reason NOT to go that way, I would go for the wider tire as it is a standard +1 upgrade. I truly believe it would be the best way to go.




Home > Products > ON ROAD > BT-45V / BT-45



ÔÇó Infomation for Safety Use of MC tires
ÔÇó MC Tire Designations



In fields of tire size, index of "TT" and "TL" shows as follows.
TT : Tube Type
TL : Tubless type



BATTLAX BT-45 is a touring type tire offered in both H and V rated speed symbols. BATTLAX BT-45 gives all-round street performance, with the emphasis on riding comfort, long mileage, wet performance, all designed by the latest tire developing technologies of Bridgestone. With the comprehensive tire sizes, BATTLAX BT-45 replace BATTLAX BT-35 and BT-17V.


Front
Rear

Technical Features

BT-45V
[Compound, pattern and shape]
ÔÇóSame high performance as the BT-45.

[Construction]
ÔÇóIncorporates Sports Sact (rear tire). Provides the same high level performance as the BT-45, but the extra potential of the V range specifications tolerates an even higher speed range.

BT-45
[Compound]
ÔÇóBattlax BT-45 rear contains Dual Tread Compound (DTC). The center compound secures long mileage and durability, while the tread edge compound secures grip and traction in corners. Also, Battlax BT-45 compound contains Silica for additional wet performance.

[Pattern]
ÔÇóThe newly developed zigzag center grooves promise high speed stability. The smaller, directional grooves in front tire effectively remove water for wet performance.

[Profile]
ÔÇóDesigned with CTDM, the unique sidewall profiles of Battlax BT-45 give high speed stability and riding comfort by cushion effect The large crown radius also contributes to the stability in high speed touring.


BT-45V Front

Tire Size Rec. Rim Rim Width OD TW
(inch) (inch) (mm) (mm)
110/90-16 M/C 59V TL 2.50 2.15 - 3.00 604 111
120/80-16 M/C 60V TL 2.75 2.15 - 3.00 598 121
110/80-17 M/C 57V TL 2.50 2.15 - 3.00 608 107
100/90-18 M/C 56V TL 2.50 1.85 - 2.75 637 100
110/80-18 M/C 58V TL 2.50 2.15 - 3.00 633 107
110/90-18 M/C 61V TL 2.50 2.15 - 3.00 655 111
100/90-19 M/C 57V TL 2.50 1.85 - 2.75 663 100

BT-45V Rear

130/90-16 M/C 67V TL 3.00 2.50 - 3.50 634 138
150/80-16 M/C 71V TL 3.50 3.00 - 4.00 646 154
120/90-17 M/C 64V TL 2.75 2.15 - 3.00 642 121
130/90-17 M/C 68V TL 3.00 2.50 - 3.50 664 135
140/80-17 M/C 69V TL 3.50 2.75 - 3.50 656 143
150/70-17 M/C 69V TL 4.00 3.50 - 4.50 641 149
120/90-18 M/C 65V TL 2.75 2.15 - 3.00 673 121
130/80-18 M/C 66V TL 3.00 2.50 - 3.50 663 131
140/70-18 M/C 67V TL 4.00 3.50 - 4.50 652 145
140/80-18 M/C 70V TL 3.50 2.50 - 3.50 681 143
150/70-18 M/C 70V TL 4.00 3.50 - 4.50 670 150



BT-45 Front

100/90-16 M/C 54H TL 2.50 2.15 - 2.75 586 100
100/80-17 M/C 52H TL 2.50 1.85 - 2.75 595 100
110/70-17 M/C 54H TL 3.00 2.75 - 3.50 589 106
110/80-17 M/C 57H TL 2.50 2.15 - 3.00 608 107
120/70-17 M/C 58H TL 3.50 3.00 - 3.50 605 123
90/90-18 M/C 51H TL 2.15 1.85 - 2.50 619 89
100/80-18 M/C 53H TL 2.50 1.85 - 2.75 617 100
100/90-18 M/C 56H TL 2.50 1.85 - 2.75 637 100
100/90-19 M/C 57H TT 2.50 1.85 - 2.75 663 100
90/90-21 M/C 54H TT 2.15 1.85 - 2.50 702 92
90/90-21 M/C 54H TL 2.15 1.85 - 2.50 702 92

BT-45 Rear

130/90-16 M/C 67H TL 3.00 2.50 - 3.50 636 132
110/90-17 M/C 60H TL 2.50 2.15 - 3.00 630 110
120/80-17 M/C 61H TL 2.75 2.15 - 3.00 624 121
130/70-17 M/C 62H TL 3.50 3.00 - 4.00 617 136
130/80-17 M/C 65H TT 3.00 2.50 - 3.50 638 131
130/80-17 M/C 65H TL 3.00 2.50 - 3.50 638 131
140/70-17 M/C 66H TL 4.00 3.50 - 4.50 627 145
150/70-17 M/C 69H TL 4.00 3.50 - 4.50 641 149
110/80-18 M/C 58H TL 2.50 2.15 - 3.00 633 110
110/90-18 M/C 61H TL 2.50 2.15 - 3.00 655 110
120/80-18 M/C 62H TL 2.75 2.15 - 3.00 654 120
130/70-18 M/C 63H TL 3.50 3.00 - 4.00 637 128
140/70-18 M/C 67H TL 4.00 3.50 - 4.50 652 145
150/70-18 M/C 70H TL 4.00 3.50 - 4.50 668 149

Please consult your local Bridgestone representatives for product availaility and legal conformity.





:dance:dance:dance
Click to expand...

Once again Lee, thanks for taking the time to help. My decision regarding 120/90 vs 130/90 was easy as there were no 130/90-18 inch available from Motorcycle Superstore (was also not in your listing).

I ordered the 120/90-18 BT45V for the rear, 100/90-18 BT45V for the front. I'm eager to see if the difference between the S11 front vs BT45 front is noticeable to me.

I can appreciate the difference when replacing worn tires with new tires. Something I had not remembered from my previous riding days decades ago. Perhaps I was too young and foolish to notice.

Regards,
Pete
 
I had suggested 130/80V-18, not 130/90V-18.

But I'm sure you will be very happy with the stock size and the performance (with the possible exception of tread mileage) of the new tires.

Give us an update as to your impressions after you've got a few hundred miles on them and they are thoroughly scrubbed in.



:dance:dance:dance
 
Howdy Pete - is that one of the less common, rear-drum white '88 K75C with T fairing conversion?
 
Ted said:
Howdy Pete - is that one of the less common, rear-drum white '88 K75C with T fairing conversion?
Click to expand...

Ted (aka Mr. Thoughtful),

I had to chuckle when reading the query. That is the million dollar question! I'm the 3rd owner and am 90% positive it is a K75 (standard). I had gone almost a year thinking it was an '88 K75C until contacting the previous owner (whom I know well). The previous owner installed the fairing and heated hand grips, so it makes sense that it is the K75 standard.

There are confusing things on the bike, like the sticker on the panel under the seat that indicates a 130/90-17 rear tire. The problem is that I've got an 18 inch diameter rim using 120/90-18 tires. So something is surely amiss.

Pictures that I've seen of the "C" model have shown a different headlight enclosure. My headlight enclosure looks more like the standard K75 (at least from the pictures I've seen).

I'm assuming you saw my profile picture of the bike (white tank with rear drum brake). That picture doesn't accurately show the red trim line on the tank. That tank is identical to the "Special Edition" K75C you might be referencing (picture attached).

Pete (aka Mr. my wife would never call me "Thoughtful")
1988 K75 Tired but loyal.
 

Attachments

  • K75C SpecEd.jpg
    K75C SpecEd.jpg
    30.4 KB · Views: 68
It does seem to be a puzzler - the 18" rear was the drum configuration, only available on the '86 & '87, and special '88 edition K75C and the '86 & '87 K75T. The only combo of 18" rear and low seat was the SE white '88 K75C. It looks like you have the headlight surround of the K75T, but again it looks like you might have the "C" bars and not the higher "T" bars like later fitted to the RT. My immediate thought was it was a K75C SE that has had an unfortunate instance with the "C" fairing (as many did).

Try this - it is a free BMW Vin decoder. Should be able to tell you the original configuration.
 
Last edited:
Response from Bridgestone

Here is Bridgestone's response regarding the tire recommendation. It is exactly as Lee Fulton suggested, an original equipment replacement with additional specific reasoning.

Mr. Giarratano,

It appears that the reason the S11 is recommended for the older models and the BT45 is recommended for the newer models is because there was a change in the speed rating of the original equipment tire that came on the motorcycle when the size was changed. The S11 has an H speed rating, whereas, the BT45 has a higher V speed rating in those sizes. Since you have the model that came with the H speed rating, it would be acceptable to move up to the V-rated BT45 to get some increase in performance. I hope this helps.

Thanks,
Adam Kaempf
Sales Engineering Manager - Consumer Products
Quality Division: Voice of the Customer
Bridgestone Americas Tire Operations
 
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