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.

In converting my 300L to tubeless last year, I also thought 2.15 on the front would be OTT, but it's fine. As J-Mo said, proper TL rims with the vital sealing bead don't come in the narrow factory widths used by Japanese 250/300 trail bikes. I think Honda choose as thin/light as possible on these bikes for good review performance and low weight figures, but fatter can work better irl.

Be warned though; it's an expensive process which can take months: new rims, hubs (buy from US), lacing and then sealing (which you can DIY) and of course, new TL tyres. I'm not sure I'd bother for domestic day-rides, but for solo overseas travel, it's another matter.
I rushed my DIY sealing, using individual blobs on each spoke (as on many previous TL conversions) but didn't let it cure properly for a day or two, and paid the price. (Tip: avoid puncture sealing fluids like Slime; they may react badly with the spoke sealant and 35°C heat.)
Expecting such problems, I bought some Puraflex 40 sealant with me, and in Marrakech a mechanic did a clean up and re-seal, this time using a continuous band of sealant (not individual blobs). While blobs are better for targeting individual spoke nipple leaks, you also raise the chances of an errant leak by ~36:1 over a continuous band.
As it is, if done well, I've never had a TL spoke leak, nor bent/broken a spoke in decades, but in future will take the continuous band route (like CWC Airtight or Bartubless). If nothing else, it's a lot less time consuming. Probably not needed but adding stretch-free tape round the circumference of the band will resist lifting.

It's true that front flats are a lot rarer, but as I was changing my front to a 19, TL was no added complication and I can leave the levers are home.

I deliberately chose AX41s as close to the stock tyre width, thinking the 300L would do without the extra drag/weight, but though I hate to admit it ;-) fatter rides better on the road, and on the dirt I can't tell at my donkey speeds. Plus as J-Mo also found, a fatter/taller rear on a smaller ø 17 works out same height as original 18er, so speedo reading is back to 8% factory error, and also the gearing drops back down to standard; a nice low 1st.
Below, my link-lowered 300L on fatter-than-stock 17/19 Mitas E07 TLs after wearing out AX41 TLs in 10,000kms. Fat front was all I could buy in Marrakech and felt a bit heavy off the bat, but bike now runs great on the road and fine on the piste for what I do.

__________________
Morocco Overland 4 (2025) • Trans Morocco Trail

Flats !!
Am i right in thinking you can still use a tube with a tubeless conversion ?
I did see a report that a puncture happens every 75,00 to 80,00 miles ?
I always use "slime " in my rear tyre , as fronts are easy to repair .and take a spare tyre inflator , tubes , electric pump and some good luck !
K

Yes, if you've punctured the [tubeless] tyre so much that it can't be plugged, you can always remove the tyre in the usual way, remove the tubeless valve from the rim, and fit an inner tube to get you going again.

fwiw. it's a wise precaution to take a tube anyway on a longer-distance trip, particularly if your route includes a lot of [typcially rocky] off-road miles, since while 99% of punctures tend to be a small object like a nail or screw which leave a hole that can be plugged with a gummy worm or similar, there is always the chance that you'll slice a tyre which is unlikely to be able to be plugged.

Jx

As Jmo says, yes you can put in a tube.
I find the phrase "puncture happens every 75,00 to 80,00 miles" somewhat hilarious! WHO decided that - based on what? Based on riding where? Or is it a car figure based on commuting somewhere?
Sorry but it has NO relevance to travelling the world on a motorcycle.
If you stick to paved roads in Europe, your figure will be vastly different than riding through the Acacia thorn-ridden "roads" of Sudan and Ethiopia. Also, how far do you push your luck on tread wear? Makes a difference.

I'm NOT a fan of slime for regular use. ANY tire manufacturer will tell you the same. Biggest issue that I'm 100% in agreement with that they raise is that it can hide a puncture and the nail moves around with riding and destroys the tire, causing a catastrophic loss of air instead of the usual more gradual loss of air with a nail puncture, particularly with tubeless.

Also, NO shop will want to have anything to do with a slimed tire replacement - or they'll charge an arm and a leg to do the job. Finally, you can't plug a slimed tire, the plug won't stick well. And same issue with patching a tube, you can't patch it reliably, the glue doesn't stick. Cleaning to get it to work is very difficult.

And of course, thinking world trip, what do you do when it's time to replace the tire / tube? No slime available probably, so back to basics.

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

Thank you again all for the responses. I bought tubeless rims from Haan in the original 18 and 21 inch (but with widths of 2.15 and 2.50). I'm away at the moment so haven't had a chance to fit them to the little CRF. However, I also got tubeless rims for my T7 for a Kyrgyzstan to Bangkok (via China) trip (from Bart factory) and they performed flawlessly. I am sold on the benefits of tubeless over tubed. I will update once I get home and fit the new rims on the Honda .

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.

Is there any tour description available?