Hello DTT community! My question is simple. Can a rear wheel be laced on a front hub? If so, has anyone done it and do you have pictures of the end result? The rear tire is currently 4.00 and I'd like to see what that would look like on both the front and rear. I just acquired a 1969 Honda CB350 and I'm leaning towards a brat style. Thanks in advance and I look forward to posting the project pictures soon.
CB350 - Can a rear wheel be laced on a front hub?
- Thread starter Gilbert
- Start date
Maybe, if the hubs were similar in diameter, width, and did not have different offsets, but the more pertinent question is; why? Adding that much rotational mass to the front wheel of a small bike like that will have it not only handling like crap, but braking will be drastically reduced.
The answer is yes and no. doc-rot just checked the right boxes.
First, if the goal is purely cosmetic, be prepared to get some flack as that usually means you are willing to sacrifice performance and de-facto safety for vanity.
That said, doc-rot is right. The main issue with the swap is hub diameter. Rims are drilled/punched/machined/formed with the holes "aiming" for a spot on a particular size hub. There is some latitude, but generally you can not take a drum brake rear rim and properly lace it to a much smaller disc brake front hub. You can buy correct length spokes, and physically put it together, but when you tighten the spokes you will see that they now have to bend. The nipple will sit in the rim and force the rim end of the spoke to aim at the much larger hub diameter and now the spoke will have to bend inward to the small disc hub. If you have a drum brake on the front, likely it will be fine with the right spokes.
Nothing wrong in my view with Brat style, and the street makes an exceptionally poor race track, but be advised that putting a larger section much heavier front tire on your bike will have a very noticeable and derogatory impact on how your motorcycle drives. It will be very noticeable even at cruising around and in town speeds. (opinions vary - "very noticeable" to some is "who cares, big deal" to others). Not that on its own (I see a lot of brat style bikes that have way, way more alterations - most for the worse) that mod will make an unsafe bike, and you may be fine with how it drives (until you hop on an otherwise "unmolested" bike), but I go with the theory that the better it works, the safer it is.
In any event - post your build!
First, if the goal is purely cosmetic, be prepared to get some flack as that usually means you are willing to sacrifice performance and de-facto safety for vanity.
That said, doc-rot is right. The main issue with the swap is hub diameter. Rims are drilled/punched/machined/formed with the holes "aiming" for a spot on a particular size hub. There is some latitude, but generally you can not take a drum brake rear rim and properly lace it to a much smaller disc brake front hub. You can buy correct length spokes, and physically put it together, but when you tighten the spokes you will see that they now have to bend. The nipple will sit in the rim and force the rim end of the spoke to aim at the much larger hub diameter and now the spoke will have to bend inward to the small disc hub. If you have a drum brake on the front, likely it will be fine with the right spokes.
Nothing wrong in my view with Brat style, and the street makes an exceptionally poor race track, but be advised that putting a larger section much heavier front tire on your bike will have a very noticeable and derogatory impact on how your motorcycle drives. It will be very noticeable even at cruising around and in town speeds. (opinions vary - "very noticeable" to some is "who cares, big deal" to others). Not that on its own (I see a lot of brat style bikes that have way, way more alterations - most for the worse) that mod will make an unsafe bike, and you may be fine with how it drives (until you hop on an otherwise "unmolested" bike), but I go with the theory that the better it works, the safer it is.
In any event - post your build!
I appreciate the responses. I'm looking at the bike and just feel the front tire is way too small after I removed the fenders. I'd like to keep the tire size somewhat uniform. The front tire is 3.00 x 18 and the rear is 4.00 x 18. Using the factory rims, is there an in between size tire I can use? Thanks again in advance.
Tune-A-Fish
BOTM LOSER Proudly Deplorable
I think you will be fine with small changes as long as you are not as Doc and Mobius say... bending spokes... it's much more sensible to increase the rim width an inch than to just put a bigger tire on to match the rear, 18 - 18 is really not a bad handling setup for cruising around town, just don't expect to carve corners, do stopies and stop like a modern sport bike. I would suggest very sternly that you get a fresh cut on the drum and use EBC Sintered Metal Grooved Brake Shoes (if available) they wont last forever but bite nicely when you need a little extra brake power.
Post up the machine mang!
Post up the machine mang!
Gilbert said:
Just an FYI but the fender acts a fork brace, and makes a noticeable difference in handling. that being said, it appears form is more important than function here. I would just throw a 4.00 tire on the front. It really wont make much of a difference at that point whether or not your rim is the correct size for the tire, cause it will be sloppy either way.
Tune-A-Fish
BOTM LOSER Proudly Deplorable
doc_rot said:
Seriously though, Doc NOT discrediting here, but are you speaking from experience, have you ridden a CB350 cycle with sloppy tires? I rode the shit out of one back in the late 70's... The whole bike is sloppy if you want to get technical... It's no H2 wobbly, but if it had power it would be down right scary :-\
The fork brace is a necessity, even if you just grind the rivets and use the bracket... do it. The rims are 1.85/2.15 I would run the 2.15 front and back without blinking an eye and run both ends wearing a 100/80/18 The speedo will be off by a mile or two less hr, if it freaks you out because of the advice, run the skinny rim and 90/90... is it best case... Honda would of done it if it were... will you wobble down the road, I doubt very seriously you will, but I also would run a decent head shake preventer, but I wouldn't ride anything without one with my reaction time these days. BIG DISCLAIMER... ALWAYS BALANCE YOUR TIRES and check that the bead is evenly distributed beforehand
I appreciate the information. I never thought about the brace. That being said, in your opinion, what size tire would give me a nice uniform look that would be both functional and safe? So it is safe to say that the bikes with those balloon tires ride like crap? As per what I've been reading so far, I would say yes.doc_rot said:
Tune-A-Fish said:
No worries Tune, i'm not ruler of the internet, lol. I have never ridden a cb350, so i don't have any direct experience, However i do have empirical evidence from riding a kz400 with oversized tires and it was sloppy to say the least. You're right, the cb350 is no performance machine, even with good tires its probably sloppy. That being said, i still think they guy should be informed of the effects of adding mass to the wheels. If there is anywhere i would not add weight to a bike its the wheels. In reality, if you go up a tire size or two its not going to make a huge difference if the bike is being ridden casually. Show, go, or cruise; everyone has a different priority when it comes to bikes, but if you are going to downgrade your bikes performance I think you should be cognizant of the fact.
alzcbz
Been Around the Block
Not to get into the balloon tire issue, but is there really much difference in the holes drilled into a rear 1.85x18 rim and the front 1.65x18 rim?
When purchasing rims from say, MikesXS, they don't differentiate between front and rear.
http://www.mikesxs.net/product/34-3182.html
Their description even says that they run the 2.15 on the front and rear of their XS400.
Disclaimer: I'm no wheel expert.
When purchasing rims from say, MikesXS, they don't differentiate between front and rear.
http://www.mikesxs.net/product/34-3182.html
Their description even says that they run the 2.15 on the front and rear of their XS400.
Disclaimer: I'm no wheel expert.
Tune-A-Fish
BOTM LOSER Proudly Deplorable
You know... with some minor mods you can shoehorn a CRF450 motor into a CB350 chassis 
then run supper motard wheel tire setup with the forks off the CRF also!! You will just need to lighten and strengthen the frame correctly to keep it from collapsing Mono shock and Pro Link any one LOL
then run supper motard wheel tire setup with the forks off the CRF also!! You will just need to lighten and strengthen the frame correctly to keep it from collapsing Mono shock and Pro Link any one LOL
Tune-A-Fish
BOTM LOSER Proudly Deplorable
alzcbz said:
There absolutely IS a significant difference. I am speaking of rims I personally purchased from Mikes. The rims were fine - no complaints. Not the finest rims out there, but very nice for the money, and I would not hesitate to buy more. That said, it is a matter of degree as to how much different the hub diameters are from the correct diameter the spoke holes in the rim are drilled for and whether or not the assembly is acceptable. MikesXS did in fact differentiate between front and rear rims. Not sure if they did so for every one they list, or if they still do so at all, but they definitely did in the past on at least some rims. The thing is, there is not actually a "front" or "rear" type of rim. It is just that most old 70's bikes had a drum rear wheel needing the rims drilled for that and disc front wheel needing rims drilled for the much smaller hub. MikesXS are not wheel builders, they just suggest what the rim should fit - i.e. an XS 650. Their product line has expanded way beyond having parts exclusively for the 650, so I suppose that has caused some confusion as to what fits what and how things are described. There is no doubt there is some uncertainty of the correct application when buying some of their rims for a bike other than they state!
