Slick options for F3 250

[richban]

I was more talking about the rear 160. I didn't pay attention to the talk about the front tyre, I ran a 120 on the front of an RGV VJ22. I wasn't very fast on the track on the thing, was mint on the road though.

A 120 70 on a 3" rim can ad a lot more circumference than a 110. In turn that would push the trail longer.

Maybe a 120 on the front and a 160 on the rear might not be so bad. I suppose it would come down to what the contact patch was like when it was pushed into a corner on hard brakes and gassing it real early out.

I really don't know.

[Drew]

I really don't know.

Nor do I. Jay is one of very few people I would take at his word on the subject.

On a big bike it's different, I gots me some sperience wit dat shit.

[neil_cb125t]

Yeah my front is 3.0, rear is 4.5. I've used a 120 racetec in the past and the profile was definitely not right. It seems to be a mission to find a 110 front...

Yeah no, the Dunlop 120s are much taller in profile like a 120/70, Meaning its tips in way nicer than a std 120/50 or 60. As the tyre is taller more pointy

The 120 front also last years.... literally

[gixerracer]

Nor do I. Jay is one of very few people I would take at his word on the subject.

On a big bike it's different, I gots me some sperience wit dat shit.

Really please explain your sperience yo have (crashing don't count)

[Drew]

Really please explain your sperience yo have (crashing don't count)

I know what I crashed earlier with.

[JayRacer37]

I run std sized ZXR400 rims on my F3 bike - what size is your front rim? The Dunlop 160 rear slick is the best out there by far, but the most expensive. I run the 120 front and have no problems but im sure my front rim is 3.0 inch. The 160 is a tad wide on the rear rim ( I really need a 5.0 inch) but the profile of the slicks still work fairly well........at taupo anyway :-)

I disagree!

Jayracer37 is the man to talk to.

The Bridgestone slicks are made specifically for the 250 proddy bikes of old I believe.

I know of one guy who had a meltdown at a bike shop, because his mate told him differently to this. But Jay knows his shit and the guy in question is as slow as a wet week anyway, and could run on cross ply tires without sacrificing his lap times at all.

That's exactly what I found when searching. Seems a bit stupid.

I agree with your earlier comment about not wanting to mess up the feel of the bike. I've put a lot of effort (and money!) into the suspension so don't want to throw it away with tyres that aren't right just because they are slicks.

But if there were some that fit, I would be very interested...

Oh and Drew, quite a few of the older 250s run a 3.5 inch front (which suits the 120 just right), but early RS250, RGV, and all NSRs run the smaller rims. So could be the case that they are in fact designed for the later bikes? Maybe? I hope to be wrong on that.

Unfortunately you are correct on this one. What we have is a 250GP tyre, to suit a 3.5" front and a 4.5 - 5" rear. This was developed around the GP bikes in the late 90's/early 00's and is perfect for that chassis architecture. In that respect, the 250 proddie bikes (ie RGV, NSR, KR1 - 'real' 250 proddie not superlite) are the right weight and geometry to work these tyres. The issue is the rims are not the same width as the GP wheels, although when run front and back (not one or the other) feedback I have had is very positive both feel and grip wise when compared to DOT tyres. Yes, there is a 'chicken strip' on the tyre, but with the pressures you are able to run on the slick (quite low) the contact patch is not compromised. Sadly, the 110/150 slicks have been discontinued, although the wets are still produced in small numbers (hence you finding info on them). Also, Bridgestone is pretty bad at updating their site so some of that information is outdated. We can get wets to special order but no availablity on the slicks at this point (though I will ask Bridgestone again for you, if you like?)

I know people do run the 120 and 160 on the 3 and 4.5 rims. I would like to try them both but as I am a cheap ass I may never know.

If you are keen to give them a go I may have a knackered rear and OK front I could lend you for a go from the GSX1100 postie racer? It does root rears though as the construction is too light for that bike.

A 120 70 on a 3" rim can ad a lot more circumference than a 110. In turn that would push the trail longer.

Maybe a 120 on the front and a 160 on the rear might not be so bad. I suppose it would come down to what the contact patch was like when it was pushed into a corner on hard brakes and gassing it real early out.

I really don't know.

Agreed. Just on the front changes geometry, while if you do both the feel is pretty good. Regarding contact patches, because the slick can be hot it can be run low (28F/24R hot if necessary) expanding the contact patch - because the bikes are light they also don't load the tyre too badly, which could compromise stability and flickability. For example, a 110/70 has an OD of 590mm (+/-1mm) so is 5mm steeper (half OD difference based on axle position) in the front immediately. You can tune this out with fork heights.

Nor do I. Jay is one of very few people I would take at his word on the subject.

Thanks mate!

Yeah no, the Dunlop 120s are much taller in profile like a 120/70, Meaning its tips in way nicer than a std 120/50 or 60. As the tyre is taller more pointy

The 120 front also last years.... literally

Our fronts are a 120/600 (600=OD, very similar to a 120/70 percentage measurement, just more accurate than using a percentage - handy on the rear for calculating ride height changes a tyre may make). 120/60 was only used in early model 600SS bikes and was discounted apart from SV650's (and similar) in about '03. Most every sports bike (or road radial using bike) uses a 120/70 front - again, in our slick sizing we call that a 120/600.

We also have options in the 'Stones - a 120/600 which is the 250GP tyre, and a 125/600 which is a Superbike tyre. Steeper, faster on the side, stiffer for higher loads - it needs a different style to ride it.

As you say, fronts last ages - I was doing 8 days on the front of the R1 and then wimping out 'cos they shouldn't last that long!

[richban]

I disagree!





Unfortunately you are correct on this one. What we have is a 250GP tyre, to suit a 3.5" front and a 4.5 - 5" rear. This was developed around the GP bikes in the late 90's/early 00's and is perfect for that chassis architecture. In that respect, the 250 proddie bikes (ie RGV, NSR, KR1 - 'real' 250 proddie not superlite) are the right weight and geometry to work these tyres. The issue is the rims are not the same width as the GP wheels, although when run front and back (not one or the other) feedback I have had is very positive both feel and grip wise when compared to DOT tyres. Yes, there is a 'chicken strip' on the tyre, but with the pressures you are able to run on the slick (quite low) the contact patch is not compromised. Sadly, the 110/150 slicks have been discontinued, although the wets are still produced in small numbers (hence you finding info on them). Also, Bridgestone is pretty bad at updating their site so some of that information is outdated. We can get wets to special order but no availablity on the slicks at this point (though I will ask Bridgestone again for you, if you like?)




If you are keen to give them a go I may have a knackered rear and OK front I could lend you for a go from the GSX1100 postie racer? It does root rears though as the construction is too light for that bike.



Agreed. Just on the front changes geometry, while if you do both the feel is pretty good. Regarding contact patches, because the slick can be hot it can be run low (28F/24R hot if necessary) expanding the contact patch - because the bikes are light they also don't load the tyre too badly, which could compromise stability and flickability. For example, a 110/70 has an OD of 590mm (+/-1mm) so is 5mm steeper (half OD difference based on axle position) in the front immediately. You can tune this out with fork heights.



Thanks mate!



Our fronts are a 120/600 (600=OD, very similar to a 120/70 percentage measurement, just more accurate than using a percentage - handy on the rear for calculating ride height changes a tyre may make). 120/60 was only used in early model 600SS bikes and was discounted apart from SV650's (and similar) in about '03. Most every sports bike (or road radial using bike) uses a 120/70 front - again, in our slick sizing we call that a 120/600.

We also have options in the 'Stones - a 120/600 which is the 250GP tyre, and a 125/600 which is a Superbike tyre. Steeper, faster on the side, stiffer for higher loads - it needs a different style to ride it.

As you say, fronts last ages - I was doing 8 days on the front of the R1 and then wimping out 'cos they shouldn't last that long!

Super helpful. Thanks! May well take you up on the offer when track ready. Ledge.

[sharp2183]

I disagree!





Unfortunately you are correct on this one. What we have is a 250GP tyre, to suit a 3.5" front and a 4.5 - 5" rear. This was developed around the GP bikes in the late 90's/early 00's and is perfect for that chassis architecture. In that respect, the 250 proddie bikes (ie RGV, NSR, KR1 - 'real' 250 proddie not superlite) are the right weight and geometry to work these tyres. The issue is the rims are not the same width as the GP wheels, although when run front and back (not one or the other) feedback I have had is very positive both feel and grip wise when compared to DOT tyres. Yes, there is a 'chicken strip' on the tyre, but with the pressures you are able to run on the slick (quite low) the contact patch is not compromised. Sadly, the 110/150 slicks have been discontinued, although the wets are still produced in small numbers (hence you finding info on them). Also, Bridgestone is pretty bad at updating their site so some of that information is outdated. We can get wets to special order but no availablity on the slicks at this point (though I will ask Bridgestone again for you, if you like?)




If you are keen to give them a go I may have a knackered rear and OK front I could lend you for a go from the GSX1100 postie racer? It does root rears though as the construction is too light for that bike.



Agreed. Just on the front changes geometry, while if you do both the feel is pretty good. Regarding contact patches, because the slick can be hot it can be run low (28F/24R hot if necessary) expanding the contact patch - because the bikes are light they also don't load the tyre too badly, which could compromise stability and flickability. For example, a 110/70 has an OD of 590mm (+/-1mm) so is 5mm steeper (half OD difference based on axle position) in the front immediately. You can tune this out with fork heights.



Thanks mate!



Our fronts are a 120/600 (600=OD, very similar to a 120/70 percentage measurement, just more accurate than using a percentage - handy on the rear for calculating ride height changes a tyre may make). 120/60 was only used in early model 600SS bikes and was discounted apart from SV650's (and similar) in about '03. Most every sports bike (or road radial using bike) uses a 120/70 front - again, in our slick sizing we call that a 120/600.

We also have options in the 'Stones - a 120/600 which is the 250GP tyre, and a 125/600 which is a Superbike tyre. Steeper, faster on the side, stiffer for higher loads - it needs a different style to ride it.

As you say, fronts last ages - I was doing 8 days on the front of the R1 and then wimping out 'cos they shouldn't last that long!

Super useful information there. Correct me if you disagree, but it seems that on the basis of all the information the slicks are not 'quite' right for the bike. In this case, going for a super sticky DOT tyre (thinking the SC1 Supercorsa here) is probably going to provide very close to the same level of grip, and will not compromise the feel of the bike. Right? Wrong?

Just to throw a spanner in the works, if I was to source a 3.5 inch front... would the balance between that and the standard 4.5 rear work well? Considering that option at this stage too.

[JayRacer37]

Super useful information there. Correct me if you disagree, but it seems that on the basis of all the information the slicks are not 'quite' right for the bike. In this case, going for a super sticky DOT tyre (thinking the SC1 Supercorsa here) is probably going to provide very close to the same level of grip, and will not compromise the feel of the bike. Right? Wrong?

Just to throw a spanner in the works, if I was to source a 3.5 inch front... would the balance between that and the standard 4.5 rear work well? Considering that option at this stage too.

No I don't disagree. They are best on a slightly wider rim. In saying that, as a matched pair the feeling should be very good, and grip will be also. The exact rim fitment information on the slicks is not available (again Bridgestone's website being a little unmaintained) but the 120/600 front and the 165/630 rear are appropriate for a 3-3.5" front and 4.5-5.5" rim respectively, so fit into what the NSR and RGV use. The best comparison I can give for exact sizes is their page for BT003-RS;

(link http://www.bridgestone.com/products/...x/bt003rs.html ) scroll to bottom for sizes.

As you can see the '160' rear is actually 164, and the '150' is a 161, so a 165 (accurate) slick is very close. Also the OD's are very similar. This also shows the 120/70 front and the fact that it is a fit for a 3" rim.

If you got a 3.5" front rim, the Bridgestone slick in 250GP construction would be the best tyre available on those bikes, matched with a 4.5" rear rim.

[Drew]

If you got a 3.5" front rim, the Bridgestone slick in 250GP construction would be the best tyre available on those bikes, matched with a 4.5" rear rim.

Which for an RGV, can be sourced straight from a bandit or RF, requiring new bearings and your old disks fitted.

Bless the lazy fuckers at Suzuki I say!

[JayRacer37]

Which for an RGV, can be sourced straight from a bandit or RF, requiring new bearings and your old disks fitted.

Bless the lazy fuckers at Suzuki I say!

Yeah, they're nice like that! Or an Aprilia RS250, they use a 3.5" rim to begin with.

[sharp2183]

Yeah, they're nice like that! Or an Aprilia RS250, they use a 3.5" rim to begin with.

Only the 2nd generation ones. Before 98 they used a 3 inch front...

[JayRacer37]

Only the 2nd generation ones. Before 98 they used a 3 inch front...

Yes, bit of mass generalisation for a Thursday! (did you check wikipedia like me to verify that one?)

[sharp2183]

Yes, bit of mass generalisation for a Thursday! (did you check wikipedia like me to verify that one?)

Nope, but my brother has one in the garage that sure as shit doesn't have a 3.5 front!

[sharp2183]

To anyone who was interested, I ended up sourcing a 3.5 inch front for the NSR, and bought a pair of the slicks Jay was referring to. Weather permitting I should have the bike out this weekend and will have more feedback soon.

(Also have a spare set of standard wheels with supercorsas 110/150 on them, so if time permits will do a direct comparison).