Hi all.
Wanting to change over to tubeless wheels on my Honda CRF250 Rally. The company I found that does them only do a front rim width of 2.15 (stock is 1.6) and the rear of 2.5 (stock is 2.15). I am fine with the wider rear rim, but the front seems very wide (on paper at least, as my T7 has a front rim of 1.85). What do you think? Is a front rim of 2.15 going to be as issue on the little CRF, or am I overthinking it?
Cheers.

You're overthinking it... if 2.15 is the narrowest rim you can get with a tubeless bead-seat, then that is what you're going to have to fit.

Keep in mind that even 80/100 profile tyre is still an inch wider than the actual rim, and if you're looking for an actual tubeless 21" front tyre it's almost certainly going to be a 90/90 profile and there are very few options compared to tube-type.

Also, consider whether you actually need a tubeless front wheel - and if you do, then consider going for a 19" rim which will give you much more choice regarding tubeless front tyres - almost every manufacturer makes a 110/80 x 19 profile tubeless front, and if you're riding a lot of paved miles, that is likely wear much better too.

note: certain brands (such as Bridgestone) also offer 19" front tyres in both 90/100x19 and 100/90x19 profile, as well as the slightly wider 110/80x19 profile, although be aware that not all of those thinner profile options may be tubeless.

Finally, as I mention above - consider whether you actually need a front tubeless wheel at all - most punctures which can be plugged (ie. tubelessly) are a nail or screw picked up in the rear tyre, while it's easy enough to pull the front wheel and patch/change a tube on these bikes if that ever did puncture.

for info. this is my 300L with a 19" front (with a tube) and a 17" x 2.50 rear rim with a tubeless rear tyre in 130/80x17 size:


photo. 17/19" wheels on the bike in the foreground, stock 21/18" wheels on the bike behind.

Hope that helps...

Jx

Thank you again JMo for your sage advice; as always. (I remember you from the old XT660 forum where I nearly bought your old bike!)

Always happy to help - for info. I've had these wheels* on my CRF300L for over two years now, and for general 'adventure' style riding - that is a mix of paved and unpaved roads/trails and a lot of miles, would suggest the 17/19" combo is the way to go if outright 'off-road' riding is not your priority.

*my own wheels were built on a set of new OEM hubs, laced to Excel rims by Dubya here in the USA - the rear is a 2.50 x 17" with a tubeless bead-seat, while the front is a 2.15 x 19" - which as I mentioned above is suitable for 90/100, 100/90 or 110/80 profile front tyres as desired - for info. I run a 90/100x19 tube-type Bridgestone AX41 up front as this particular 2.15x19 rim is not technically a tubeless anyway, but their 110/80x19 size tyre is.

If you were on a real budget, then I'd suggest simply getting a 17" x 2.50 tubeless rim laced to your existing rear hub, and 'ghetto tubeless' it yourself - as I did - link: here.

As long as you use proper marine grade sealant on the spokes, and good quality rim tape, you ought to have many thousands of mies of trouble-free tubeless tyre running - and note that the 130/80 x 17" rear AX41 tyre is the same diameter as the 120/80 x 18" profile stock size tyre according to the Bridgestone literature, so you're not giving any top speed/ground clearance away nor having your speedo read incorrectly either.

As for the front, as I say, personally I don't consider it essential to have a tubeless front tyre - as long as you run a decent pressure you ought to avoid pinch-flats anyway, while a penetration puncture is more likely to occur when the front tyre flicks up something sharp which is then run over by the rear.

This size 17/19" rim combo also offers a far wider choice of longer lasting all-terrain 50/50 style tread tyres, compared to more skinny 18/21" knobblies.

For info. this is a Rally with the 17/19" wheel combo Rally Raid Products in the UK sell:


photo. Rally Raid demo CRF300L Rally, with their 17" rear and 19" front wheels/tyres fitted.

...very much based on my [size] recommendation after building my own wheels, although be aware their wheels are not technically tubeless rims - so you'd be on your own regarding doing the ghetto tubeless conversion on those, since they don't have a double-lip bead seat as far as I'm aware.

Hope that helps!

Jenny x

Great post from Jenny, great points on all counts although I must take exception with the "ghetto tubeless".
I'm NOT a fan, from a safety viewpoint - without the safety bead, it ain't safe! The safety bead is there for a reason. YMMV and make your own decision, but be aware of the technical reasoning behind the safety bead.

__________________
Grant Johnson
Seek, and ye shall find.
------------------------
Inspiring, Informing and Connecting travellers since 1997!
www.HorizonsUnlimited.com

Oh I'm with you there Grant - hence making sure my 2.50 width [Excel] rim had a proper tubeless bead-seat - I wouldn't personally run one tubeless without either... although I understand some people do*.

It is not to be recommended however - *hence my 'you'd be on your own' - although concede that phrasing might come across as a nod and a wink if not an actual endorsement - which was not the intention, only as information.

As Grants says - don't do it without checking you have a proper double lip tubeless rim kids!

Jx

ps. with regard to referencing the [Rally Raid] 17/19" wheel size combo for the CRF/Rally models - it was more that those rim sizes offer a wider range of tyres more suited to longer distance all-terrain travelling (than typically skinny and soft 'dirt bike' 18/21" tyres) - so if anyone is building a lighter weight long-distance travel bike using the CRF300 models as a base (as I have), those sizes are definitely worth considering if your route is likely to include a far higher proportion of paved road riding, and give little if anything away on rougher terrain.

The only warning I'd give about using tape and/or sealant to make tubeless wheels is to clean rims thoroughly from corrosion and even more importantly properly retention them. This is usually more critical on the rear, since drive side spokes get stretched. Spokes poking holes in the tape/sealant, tape drying and falling off or getting damaged during tire mounting/dismounting are prime reasons for tape job failure. And don't use fix a flat or slime, it will dissolve the tape.

I would also suggest just doing the rear wheel conversion , since you're more likely to have a pluggable flat in the rear, and the front doesn't have the safety bead and more likely to be blown off the rim when you hit a rock. Unless you ride in the area where prickly pears are common and use MotoZ front tires which are the b!tch to mount.