Topic: Opinions Wanted: 16" Rear Wheel on a Cafe Racer

[Roach Carver]

I saw who wrote it and scrolled past. I may be bored, but not that bored.

[Terry in Australia]

That reminds me of a story about "back in the day" when we used to wear onions on our belts, but I won't tell it here, I don't want anyone saying I'm boring.........

[thelowmax]

I'm changing out the rear 130/90/17 for a new 140/90/16 on my cb750k8. I have another k8 with a rear 17, both with 19 fronts.  And a 76k with front and rear 18s. I like all the handling benefits of the various combinations as well as the styling, and have strong opinions about each. But, really I just want to show my new wheels.

[754]

Yeah them 140 s look big on a Honda 4

[Terry in Australia]

I'm changing out the rear 130/90/17 for a new 140/90/16 on my cb750k8. I have another k8 with a rear 17, both with 19 fronts.  And a 76k with front and rear 18s. I like all the handling benefits of the various combinations as well as the styling, and have strong opinions about each. But, really I just want to show my new wheels.

Watch that your centre stand doesn't chew a big chunk outta your new tire mate, I had the same size rear on my bike and nothing touched when I spun it up on the centre stand, but when I came home from my first ride, I had a 1/4" deep gouge around the side of my tire.

It turned out that the jagged inner edge of the right "foot" of the stand was rubbing against the tire, and my new 140/90 BT45 was toast.............  

[thelowmax]

I'm changing out the rear 130/90/17 for a new 140/90/16 on my cb750k8. I have another k8 with a rear 17, both with 19 fronts.  And a 76k with front and rear 18s. I like all the handling benefits of the various combinations as well as the styling, and have strong opinions about each. But, really I just want to show my new wheels.

Watch that your centre stand doesn't chew a big chunk outta your new tire mate, I had the same size rear on my bike and nothing touched when I spun it up on the centre stand, but when I came home from my first ride, I had a 1/4" deep gouge around the side of my tire.

It turned out that the jagged inner edge of the right "foot" of the stand was rubbing against the tire, and my new 140/90 BT45 was toast.............  

Watch that your centre stand doesn't chew a big chunk outta your new tire mate, I had the same size rear on my bike and nothing touched when I spun it up on the centre stand, but when I came home from my first ride, I had a 1/4" deep gouge around the side of my tire.

It turned out that the jagged inner edge of the right "foot" of the stand was rubbing against the tire, and my new 140/90 BT45 was toast.............  
[/quote]

Yikes!  Thanks Terry.  I have encountered a center stand issue before and didn't realize it until the damage was done. The old exhaust was a rotted out 4 into 4, and when I changed to a 4 into 1, didn't realize that the old pipe had a nub that rested on and prevented the center stand (when up) from dragging on the chain. Luckily it only ground off a little of the stand and didn't wreck my chain.

As for the tire... I recently bought a used 16x3 with a 150/90/16 tire on it. The tire needed replacing soon, as there was not much depth to the tread. The seller also stated that there was a little wear on the side from rubbing (after all, this is a WIDE tire, he stated over and over) Before I bought this I specifically asked if the tire was straight and balanced. The seller said it was. The first thing I noticed when I got it, was the half moon shaped wear on the edge of one side (the brake hub side). When I pointed out that a straight tire would rub ALL the way around, he refunded most of my money. Ultimately, though, I couldn't figure out what it was rubbing against to cause the damage. I checked it out with a spare swing arm and measured chain distance, but until I read your post I didn't even think of the center stand. You saved me a lot of aggravation by pointing out the obvious.

BTW, here's my solution to the dragging chain issue...

[MCRider]

I'm changing out the rear 130/90/17 for a new 140/90/16 on my cb750k8. I have another k8 with a rear 17, both with 19 fronts.  And a 76k with front and rear 18s. I like all the handling benefits of the various combinations as well as the styling, and have strong opinions about each. But, really I just want to show my new wheels.

Watch that your centre stand doesn't chew a big chunk outta your new tire mate, I had the same size rear on my bike and nothing touched when I spun it up on the centre stand, but when I came home from my first ride, I had a 1/4" deep gouge around the side of my tire.

It turned out that the jagged inner edge of the right "foot" of the stand was rubbing against the tire, and my new 140/90 BT45 was toast.............

Nothing like the wisdom of personal experience. 

[754]

We learned the hard way to save you guys the grief...

[crazypj]

Whadda you mean learned?
I'm pretty sure we are still learning to do dumb #$%* 

You never grow up, you just get older 

[Terry in Australia]

Yikes!  Thanks Terry.  I have encountered a center stand issue before and didn't realize it until the damage was done. The old exhaust was a rotted out 4 into 4, and when I changed to a 4 into 1, didn't realize that the old pipe had a nub that rested on and prevented the center stand (when up) from dragging on the chain. Luckily it only ground off a little of the stand and didn't wreck my chain.

As for the tire... I recently bought a used 16x3 with a 150/90/16 tire on it. The tire needed replacing soon, as there was not much depth to the tread. The seller also stated that there was a little wear on the side from rubbing (after all, this is a WIDE tire, he stated over and over) Before I bought this I specifically asked if the tire was straight and balanced. The seller said it was. The first thing I noticed when I got it, was the half moon shaped wear on the edge of one side (the brake hub side). When I pointed out that a straight tire would rub ALL the way around, he refunded most of my money. Ultimately, though, I couldn't figure out what it was rubbing against to cause the damage. I checked it out with a spare swing arm and measured chain distance, but until I read your post I didn't even think of the center stand. You saved me a lot of aggravation by pointing out the obvious.

BTW, here's my solution to the dragging chain issue...

Ha ha, no worries mate, I'm always happy to share my pain, there's nothing more disappointing than seeing a brand new tire with a big gouge in it.

Re: your centre-stand/chain inteface issues, I've had to make a little bracket to stop the stand from hitting the chain for most aftermarket exhausts I've fitted, but I've often thought that if I just rivet a Teflon block onto the back of the centre stand leg I could then use the assembly for a chain tensioner? Cheers, Terry.

[thelowmax]

I finally got my tires on my wheels on my bike. Phew!

I was surprised when I put the new 140/90/16 on,  that it didn't rub against the chain guard or the center stand but instead, the brake hub stabilizer arm. I bent it to wrap around. Works great.

[Terry in Australia]

Best of luck with that mate, the outer brake plate still rotates as your suspension goes up and down over bumps, and when you apply the brakes etc, so your bend will straighten out pretty quickly. Cheers, Terry.  

[Rookster]

I was surprised when I put the new 140/90/16 on,  that it didn't rub against the chain guard or the center stand but instead, the brake hub stabilizer arm. I bent it to wrap around. Works great.

A simple fix is to move the brake arm to the outside of its mount on the swingarm. Get a longer bolt and you should be all set.

Scott

[Retro Rocket]

Best of luck with that mate, the outer brake plate still rotates as your suspension goes up and down over bumps, and when you apply the brakes etc, so your bend will straighten out pretty quickly. Cheers, Terry.

I bent the stay on an old K2 years ago Terry to accommodate a 140x 18 rear tire, worked a treat. If you use your brakes "properly" you shouldn't have any problems, if you {not you specifically} are one of the ones that think your rear rake is your primary brake then it may be a problem eventually, but it worked fine for me on a very hard ridden old 750....

[Terry in Australia]

Ha ha, anyone who'd put a 140 (5.5") wide tyre on a 2.15" wide rim has probably already had an "over the handlebars" experience Mick, I hope you were wearing a helmet!

[thrutheframe]

Hi
Building a CB750 Cafe Racer with Dunstall bodywork.  What are opinions on using a 16" wheel in the back?  I am considering it.  I wanted to use an 18" wheel but I am limited by the lack of availability of 18" Lesters.  All opinions welcomed.

Here are some pics of what I am building.  My bike will have the full fairing and the 2 piece tank and seat unit not the one piece tank/seat cover.




Thanks
Scott

A 16" rear won't look right on a café.

IMO

[Shane72]

Changed out the 16" for the 18" rear yesterday...

The initial motivation was because I had a problem that manifested itself on smooth roads, between 45-60 mph, cycling, rhythmic set of bounces felt through the front end and handlebars.  I rebuilt the whole front end, went through two brand new sets of tires (thinking I had an out-of-round situation), balanced and rebalanced again, seated and reseated again...nothing.

A few weeks ago I was heading south with the setting sun on my right side when I plainly saw the problem in my shadow...the rear wheel was hopping like mad in the exact cyclic cycle of what I was feeling in my hands and the frame.  Time to concentrate on the rear wheel, and maybe the suspension as well.  I really hoped the problem was only the wheel, as my shocks are new Hagons, which I love and did not want to change.

The rear wheel was a 16" harley-style conversion rim that took a tremendous amount of weight to balance (like 3.5 ounces!), but it would balance eventually.  Yesterday, I changed it out to an 18" wheel of appropriate vintage, and put another freshly-balanced new tire on as well.

Boom!  Like butter.  That 16" wheel, though balanced, was absolutely not acting like it on the street.

The only explanation that I can come up with now is that the rim itself must not be round.  I will be putting it on the truing/balancing stand once the tire is off to find out for sure.

It also looks much better, not only to me, but also to my wife and friends that commented yesterday.  Another bonus is that the final gearing is much better, with highway speeds at a non-wailing RPM.  The difference in diameter was a good 2", and the axle now sits a full inch higher off the ground.

FWIW, and YMMV.

All the best,

Shane

[Retro Rocket]

Ha ha, anyone who'd put a 140 (5.5") wide tyre on a 2.15" wide rim has probably already had an "over the handlebars" experience Mick, I hope you were wearing a helmet!

I agree but mine was on a   3.5 DID, 140 was still a fraction wide , I had to bend the brake stay arm, it worked well and never hit the tire or straightened out.      I have a 3.5 DID here thats going on one bike, if I use the stock swing arm I may have to bend the stay again....

[Terry in Australia]

Well you could Mick, but that's a bit too "Agricultural" for me, and not using your rear brake so you don't straighten your bent stay rod is just silly.

With what you've been spending on your collection of parts that you've been amassing over the last few years that you've been a member here, I'm sure you could come up with a better solution than just bending your brake stay arm and remembering not to use your rear brake. Cheers, Terry.

[Retro Rocket]

Well you could Mick, but that's a bit too "Agricultural" for me, and not using your rear brake so you don't straighten your bent stay rod is just silly.

With what you've been spending on your collection of parts that you've been amassing over the last few years that you've been a member here, I'm sure you could come up with a better solution than just bending your brake stay arm and remembering not to use your rear brake. Cheers, Terry.

I have a rear disc hub Terry so i'll probably use that anyway, { I would probably weld on a new mounting point for a brake arm now anyway} I never said i don't use my rear brake though or didn't back then, i don't rely on it for sure, I out brake most people i ride with and like you, I have owned some very fast bikes, 90% front 10% rear, I use my rear brake mostly when riding slow, for stability, I barely use it in the wet and only lightly in the dry, front does most of the work and you know that, remember mate, I didn't get my car license til I was 40, I rode bikes almost every day of my life up until then including track days so I think I have a handle on braking....
I'm waiting on a nice big box of parts from Mr Benton so {hopefully} I should be riding something soon {instead of the missus}   

[crazypj]

I think the only bike that looks OK with 16" wheels is Ducati 160 or 1960's CD175

[thelowmax]

Best of luck with that mate, the outer brake plate still rotates as your suspension goes up and down over bumps, and when you apply the brakes etc, so your bend will straighten out pretty quickly. Cheers, Terry.

I bent the stay on an old K2 years ago Terry to accommodate a 140x 18 rear tire, worked a treat. If you use your brakes "properly" you shouldn't have any problems, if you {not you specifically} are one of the ones that think your rear rake is your primary brake then it may be a problem eventually, but it worked fine for me on a very hard ridden old 750....

It took quite a bit of effort to bend the arm. I doubt it will straighten with normal use (i.e., hard riding).

[Retro Rocket]

Best of luck with that mate, the outer brake plate still rotates as your suspension goes up and down over bumps, and when you apply the brakes etc, so your bend will straighten out pretty quickly. Cheers, Terry.

I bent the stay on an old K2 years ago Terry to accommodate a 140x 18 rear tire, worked a treat. If you use your brakes "properly" you shouldn't have any problems, if you {not you specifically} are one of the ones that think your rear rake is your primary brake then it may be a problem eventually, but it worked fine for me on a very hard ridden old 750....

It took quite a bit of effort to bend the arm. I doubt it will straighten with normal use (i.e., hard riding).

Your correct, the arm is strong and only it stops the hub rotating, all it does is moves the hub counter clock wise a bit after bending the arm....