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Discussion Starter · #1 ·
Can anyone advise me on what wheel rim will fit onto a rear of a 2007 ST Sprint 2007 model to take a 190 tyre. It needs to be a 6 inch rim made for singel side arm swing?

Does any of the Daytona 3 spoke rims fit standard onto a ST Sprint and is so does the front rim also fit onto the standard setup?

Any advise appreciated.
 

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I am sure the Daytona SSSA wheel would fit the swing arm because it is the same part, on a 955 Sprint that is.

Your 1050 could be a different matter.

However I would like to point out I have tried the 190 on a standard 5.5" rim and you will gain nothing in handling performance and the turn in will be marginally slower with the bigger back tyre.

I have the 190 on my Daytona and as you are aware the 190 is stock on that bike, but it is also about 30kilos lighter and had more aggressive steering geometry, like other litre sports bikes.

I see no advantage in using a 190 on your Sprint.
Buy a Daytona then you won't have to change wheels:D

DaveM:cool:
 

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Discussion Starter · #4 ·
Thanks Dave,

I like the look of a wider rear tyre and I also thought that a 190 would lay more rubber area on the road hence better stopping and cornering as well as accelerating out of corners.

the Daytonas are a fantastic bike but I need to ride more upright and hence why I brought a St Sprint, which for me, covers both worlds of sport and touring really well.

Looking at the geometery of tyre profile i didnt believe that the 190 on a 5.5 inch rim would do the 190 tyre or bike any justice
 

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Discussion Starter · #5 ·
I had 2000 955 Speed Triple w/ 6" and 190.
I tested fit the wheel and it fits the ST 1050 w/o issue :)
Thanks for that info Salaki,

Was the 2000, 955 speed triple a three spoke wheel?
Also did you test the front wheel?

The reason I ask is if I go to a 6 inch 190 tyre and rim I want the rims design ( 3 spoke etc) to be the same for the front wheel as well.

Please let me know - Thanks:
 

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Thanks Dave,

I like the look of a wider rear tyre and I also thought that a 190 would lay more rubber area on the road hence better stopping and cornering as well as accelerating out of corners.

the Daytonas are a fantastic bike but I need to ride more upright and hence why I brought a St Sprint, which for me, covers both worlds of sport and touring really well.

Looking at the geometery of tyre profile i didnt believe that the 190 on a 5.5 inch rim would do the 190 tyre or bike any justice
Since all the real work like stopping and cornering is done at the front and though one can spin up the rear with effort, a 190 will hinder more than help. You would really feel the difference in transitions with the 190 on it would take more effort and be quite doggy. The ST, though you can mount one on, really isn't balanced for it.
IIRC there have been in the past, people have found that they did have a 6" with the 180 from the factory and even then when trying a 190 went back to the 180.
 

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Discussion Starter · #7 ·
Since all the real work like stopping and cornering is done at the front and though one can spin up the rear with effort, a 190 will hinder more than help. You would really feel the difference in transitions with the 190 on it would take more effort and be quite doggy. The ST, though you can mount one on, really isn't balanced for it.
IIRC there have been in the past, people have found that they did have a 6" with the 180 from the factory and even then when trying a 190 went back to the 180.
Thanks Dolson for your comments and I will need to give this some very careful consideration as both you and DaveM seem to recommend against a 190 rear and with your combined experience I would have to take serious heed.

However I just wanted to air the following with you as there must be a fundamental flaw with my thinking to date which you might be abkle toi set me straight.

I took a 180 tyre profile with a 5 inch rim and drew the cross section onto my CAD system at full size. I then drew a 6 inch rim with a 190 tyre profile with the same rolling diameter and overlaid to compare the two. The results were that the 190 tyre had a slightly flatter external radius, the difference being very small but still noticable.

Now this is where I probably have this all wrong but given that the front tire would have a greater turning influence over a flatter radius rear tire which wants to turn less, it would stand to reason that the front would turn more than the rear and hence have an oversteering effect which in car geometry negative cambre gives and which is a desirable effect if it is used by a competent driver compared to oversteer. Hence why all the racing cars go fo slight oversteer and negative cambre geometry.

However a bike is a different animal to a car and I have to take your advice onboard and rethink the balance and geometry.

your thoughts and experience may shed light on this so I can understand / learn - Peter (ZZ55)
 

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Thanks for that info Salaki,

Was the 2000, 955 speed triple a three spoke wheel?
Also did you test the front wheel?

The reason I ask is if I go to a 6 inch 190 tyre and rim I want the rims design ( 3 spoke etc) to be the same for the front wheel as well.

Please let me know - Thanks:
It was the 2000 S3 w/ 3 spoke wheel.


I didn't test the front because it would take me longer time to do it. The wheel size and width is the same w/ ST 1050 except front shaft nut opening.
ST's Front shaft bolt looks smaller than the S3.

It may look smaller but the shaft would probably be the same diameter (I didn't confirm).

The way to check is check front wheel bearing part # from Triumph for 00 S3 and 05+ ST 1050. If they are the same, then the shaft diameter would probably be the same.

One thing to note is that on 00 S3, there is mechanical speed sensor on the front wheel (right side) so right bearing seal/cap might be different than ST 1050. I still think you can get an ST 1050 bearing seal it should work.

I sold my 00 S3 last night so I didn't get a chance to test it.

I love the 3 spoke design too and I wanted to powder coat it gold and slap those on my Caspian ST 1050 :) but changed my mind.

These wells are going for US$350s on Ebay so it's not that bad of a risk :p.
 

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Experience counts

ZZ55,

The Don is dead on the money (as usual):)

I can speak from experience with a Sprint and my riding is fairly brisk; that the 190 will slow your steering down on a Sprint and will slow down transition in the esses as Donski explained in more techy terms than my seat of the pants stuff.

I tried it with two 190's and went back to the 180 for quicker steering. The 190 is fine on my Daytona but it was designed for it and has more agressive steering geometry than the Sprint.

Of course you can do what ever you like with your bike but don't do it thinking a Sprint will have improved handling because it will not.

The reason I tried it was because I thought it would be better, people here years ago told me it would not and they were correct.:)

just my 2 cents worth as I already have the 190 Tee shirt so to speak.:)

cheers,
DaveM:cool:
 

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A wider rear tire isn't always better. The only reason why the R1 and the like have a 190 rear is because they have been set up and engineered for it. They need that small extra bit of contact patch for the hp they create. The rest of the bike from steering geometry to foot peg position all take into account what tire sizes are on the bike.

I took out a basic Vegas one day for a ride. It was real nice and turned as well as can be expected for a cruiser. Right after that ride I came back to the demo truck and took out the Vegas Jackpot. It has the giant rear tire but the rest of the bike is just like the Vegas.

I couldn't believe how hard I had to fight to turn that bike. It was a pure brute compared to the standard Vegas. It scared me a few times in traffic when I had to really throw the bike to get it to turn.

Yes it would be exaggerated on the Vegas compared to the Sprint but heck it does make a difference.
 

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Discussion Starter · #11 ·
Dave, Thank You for your input.

Can I say in a general term however how blown away I am with this Sprint forum and the other RAT forums.
I am new to this stuff and am overwhealmed at the great source of information so readily available, especially for me as my background is racing cars and trail bikesand have had to learn the hard and long way on those items by my self.

Having this forum and the experience of so many rides world wide of majic.

A huge Thank you to you and the other moderators for your time and efforts, please know that it is very much appreciated

Peter(zz55)
 

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I put a 190 on my sprint. It fits but I think the handling is negatively affected. The 190 was on it when I bought the bike so when I replaced the tire a few days later I put on what was already there. I wish I had the 180 cause the bike feels like it falls into corners instead of rolls into them which can get a bit scary from time to time.
 

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IMHO Bike factorys spend millions on research and development to find the tire and rim combos that work best for a particular model. If they come with a 180 rear tire then that is usually the one to stick with. counter to the assumed benefits of fitting wider tyres is the extra cost of the tyres. Unless i was at track days all the time i think that i would rather stick to the 180's and use the extra money for fuel:D
 

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IMHO Bike factorys spend millions on research and development to find the tire and rim combos that work best for a particular model. If they come with a 180 rear tire then that is usually the one to stick with. counter to the assumed benefits of fitting wider tyres is the extra cost of the tyres. Unless i was at track days all the time i think that i would rather stick to the 180's and use the extra money for fuel:D
I'd stick with the 180 anyway at the track. As mentioned much better, quicker handling so your lap times will be quicker and you won't get as tired out. The Sprint can be a lunk through transitions.
I'll take all the help I can get.
 
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