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Hey Guys...I have seen several folks that install bigger wheels...most common it seems is going to a 18" on front and a 19" on the rear...Question...How does that affect the Speedometer...?? I know when I went to Bigger wheels on the Harley it did not matter for now the Speed is read through the transmission on the Bikes...How about the cars..
As long as the overall height of the tire stays the same, (lower profile tire) then no effect on the speedo. There are post somewhere with a chart...may be able to change settings somewhere.
With a bigger diameter wheel, you would typically go down a profile size with your tire (i.e., from 275/40-18 to 275/35-19) to maintain a relatively close comparative circumference - otherwise you simply will have to live with the error factor. Also consider that conventional wisdom calls for a bigger circumference rear than front; there is some variance that you (and your car) can live with. Lots of threads on this with people relating their individual experiences. Then of course there is the matter of not all tires come in all sizes, so you may have to play around with different combinations Good luck if you choose to take the plunge.
Thanks...was Not Sure..When I went up on my old Street Glide to a 20" on front and 18 on Rear there was no Change...now Bikes get their reading from the Transmission...was Just Checking on the Cars ...Been a while since I changed things on a Car...Thanks for The info
Cars pretty much always used to get their speed reading from the transmission - that's where your old speedo cable would screw into. Same today, except it's read from a speed sensor rather than mechanically. I am running 18/19's with standard C6 tire sizes - many people run C6Z06 wheel/tire sizes. Maybe a couple mph off tops.
If you went 20's or up, you might start to be noticeably off. BTW, the traction control/ASC software expects pretty much the same front to rear rolling radius ratio as stock, hence the tendency to go for slightly larger rears than fronts.
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Originally Posted by jdvann
As long as the overall height of the tire stays the same, (lower profile tire) then no effect on the speedo. There are post somewhere with a chart...may be able to change settings somewhere.
I would agree with this. Even if there was a difference, it would be very minimal and you probably wouldn't even notice it.
It doesn't matter where the speedo picks up from, the wheel or the trans. If you change the driven wheel's diameter there will be a different reading on the speedo. Even when you changed your bike's tires you had a difference, it just was so slight that you really couldn't notice it.
when you go up to a bigger wheel...say 18 front and 19 rear...with more low profile tires..are folks having problems with bending their wheels with less rubber...or hows the ride...???
What is a Good Wheel that will bolt right on a 2002 c5 with out mods...if I go to 18 & 19's...Reason I am asking I will be in the market to replace the Tires next spring...If I have to drop a grand on tires...I should look at wheels...or a Good combo set...Maybe someone has a used package deal...always looking...Thanks
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ride quality should be fine on a lower profile as long as you get a quality tire... I am on 19's all around and 35 series tire, have had 30 series as well and both were fine... same goes for the wheels, good quality will be fine... a forged wheel is preferred but they are more expensive... I am personally not a fan of the cheaper chinese cast replica wheels but if all you are doing is normal driving and no high speed runs or track racing then honestly you probably won't have any issues... I have been tossing around the idea of selling my rear ccw 505a's and going with wider wheels/fenders but you are probably looking for a full set so I'm not sure if you would be interested in something like that, and we have no idea how much you are looking to spend either
when you go up to a bigger wheel...say 18 front and 19 rear...with more low profile tires..are folks having problems with bending their wheels with less rubber...or hows the ride...???
What is a Good Wheel that will bolt right on a 2002 c5 with out mods...if I go to 18 & 19's...Reason I am asking I will be in the market to replace the Tires next spring...If I have to drop a grand on tires...I should look at wheels...or a Good combo set...Maybe someone has a used package deal...always looking...Thanks
I went with the OEM Spyders off a C6 Z06 Lingenfelter. Bolted right on. No issues. Looks mean on those 12" rears. Ends up with a 325 back there. I love the look. No mods.
I'm running 275/30 in the front and and 305/30 in the rear on my Z with 19/20 CCW 505A setup. Using NITTO NT05's at the moment, with no mods and no breakage. I will probably need new tires by spring and I'm looking at going with Toyo T1R's this time around. I have about 9k miles on the Nittos.
Running TSW Nurburgring 18 front, 19 rears - Michelin Pilot Super Sport tires 275/30 on front 305/30 on rears. No noticeable difference in Speedo reading etc.
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Last edited by olbear1962; Dec 30, 2015 at 02:20 AM.
Question About Wheels...
Good luck if you choose to take the plunge.
