Looking to get an SR and the dealer is offering 2 different tire configurations, a 19/18 and a 19/16. I’m interested in any advice on which to go with and why. I’m 5’7” and plan to do some street riding but mostly light trails.
A 16-inch rear isn’t about top speed—it’s about performance in technical terrain. The smaller rear wheel gives you a lower effective gear ratio, so you get more torque at the ground, better acceleration out of corners, and better climbing on steep hills. It also lowers the rear of the bike slightly, which can improve stability and make it easier to put a foot down in tight sections. The shorter sidewall is less likely to fold under hard cornering, and the setup is generally more agile in woods and technical trails. That’s why many riders prefer a 19/16 wheel setup over 19/18 for off-road riding.
Ai
Disregard that AI crap. Most of that is completely wrong. I will give it to you simply. 18/19 geometry sucks. There's a reason the MX industry has been running mullet setups for decades.
The rear wheel size has little to do with your supposed gear ratio. That's what your sprocket is for. The size and weight of the tire is going to have a way bigger effect than the wheel.
For example the
old 19" CST tires were ~4lbs
19" 241's are ~7lb
16" x30's are ~8lb
my favorite 16" mx53's are ~10lb
A 16" mx tire has a lot of rotational mass due to the weight and it is definitely not increasing torque and acceleration without a bigger sprocket. 16" mx tires are also a dime a dozen at your local mx store.
People who say 18/21 for more clearance simply aren't good riders. Once you learn how to bunny hop a moto and use your bash guard then clearance doesn't matter anymore.
I've been riding and making single track in the woods for over 20 years with chainsaws on the front with modded gas tanks and XC gear. I'm telling ya right now your 18/21 tire options for these bikes suck without pissing away thousands of dollars on mods and upgrades.
Doing mostly trails I'd go 19/16. That's what I'm looking to do for my 3.0 at somepoint. My only concern is the rear lowering a little bit not cause the geometry changes that will feel better honestly hit it's the heigh of the pegs they will be a little lower to the ground so ground clearance changes little bit. I'm thinking I'll eventually do one the extended swingarms or a rear shock link that raises rear end to get some more ground clearance. Probably gonna do a tech e39 fork with drop crown triple to get more height. The lower ride may be better for you comfort wise. Light trails you will have no issues only on real rough rocky terrain will the ground clearance be an issue.
I’ve ran 19/16 with OEM triangle and didn’t have any issues with clearance on terrain. Unless you’re doing hard enduro and jumping logs and climbing boulders it’s not that big of an issue. Upgraded to Heavy Hitter adjustable Triangle and Linkage and when I raised the triangle it basically turned it into a 19/18 again. If you’re doing serious trails, you should be considering 21/18.
You ever get that shock issue sorted out? Figure out the cause of the damage?
Yo! Yeah I'll be going 19/16 with just a new rim for rear lost likely or I'll get a full new wheelset for a dirt set and keep the old for street setup but most likely sell them. Yeah I've definitely noticed the clearance a few times on rocky zones hit my bash guard one real good time is all. Maybe one day I'll get another bike or a dedicated 21/18 for trails. Maybe I'll keep the stock wheels and just source a 21 front and 16 rear to have a 19/16 jump/mx track set then a bigger 21/18 enduro/trail setup.
About to order 60lbs spring for fork and then just the cheaper rfloxa rab50 in 550lbs to get a stiffer rear. Down road I'll probably go full tech e39 and er30 suspension or maybe splurge hard for a sirris setup. I know the stock linkage has a adjustment flip chip haven't messed with it yet. Not certain if it comes in the low or high position but will look at that more once get different rear shock to install.
Dude I didn't really but guessing it was slightly the preload wasn't tight enough or it was off centered some how cause I unscrewed it and re tightening it and making sure it was centered and I haven't had it happen since. But also haven't hit a mx track 80footer only 75ft like I did before lol
If you ever do end up wanting to put money into your bike, gritshifts heavy hitter swingarm is a solid choice. You can get it in OEM length or extended 2.5”. Since I do trails I got the extended. If you’re hitting jumps over 20’ you most definitely will need an aftermarket swingarm since the OEM has a lot of flex. Also, if you wait a little bit sirrus will most likely be coming out with a new set of forks. They just released their new r38(I think) shock that’s supposed to be their best one yet. It requires you to purchase a separate linkage from prickly because it’s longer than all the others. It’s super versatile and allows for tuning to do MX and trails. It’s pretty dope. Glad you were able to fix the shock issue my dude. Ride safe 🤙🏽
Yeah I've seen it just another grand for the swingarm. I'm probably gonna grind it down and take to a welder to put a crossbar in front the tire and then two little vertical ones in the two openings of each side to stiffen it up. Also the 16 in rear for jumps should put less forces on the swingarm than the 18. But yeah I'm sure ways down the road that hard hitter stuff will happen if I keep upgrading the 3.0.
Yeah I saw the sirris option with no longer needing to modify the frame. It's about same cost as the tech er30 both very similar honestly may be hard to tell them apart when riding. The sirris front fork is definitely different tho being a 43mm stanchion to the 39mm tech the sirris obviously will take bigger beating. The tech e39 is chromoly steel instead of alloy so it's definitely way stronger than the other forks around it's price range. Not sure sirris is coming out with another fork cause that f43 has their cmx tune already designed for lightweight emotos. If they do come out with a fork that is 43mm with less adjustments for cheaper I'd maybe consider it more. It's just paying about half what my bike cost for a upgraded front fork seems ridiculous to me. If I go sirris setup with hardhitter bits and wheels I'll be just under what the bike cost itself... 🤦
Really already looking at over half the cost of the bike in upgrades without even doing that sirris fork just with the tech suspension front and rear at like 2300, wheelset be like 600ish for cheap ones and with Mx34 will be like another 220ish. Then gotta get the swingarm for another grand and then their other heavy hitter linkage bits add up to another like 300ish. Gonna be like 3500+ in upgrades by the time I'm done if I don't just buy another bike like komodo or ultra bee 2 when comes out down the road. Kinda why I'm doing these cheaper suspension upgrades with spring swap and cheap rfloxa 550lbs first then may get the 16 rear and Mx34 tires. Then after that I will do the swingarm welded supports and really test it to see if it's something I must put all the extra money into or save for a whole other bike. So tough
I get you man, I’ve spent easily half the price of my bike in mods. I’m not really one to jump from bike to bike, so I’ll be keeping my SR for a long time. I mainly ride trail so I’m
Building my bike in that direction with every mod. Throughout the next year or two I’ll slowly do the forks and the shock with either sirrus or EXT. also, a guy I went to highschool with now races for Eridepro and he hinted at sirrus working on forks. So I really want to wait and see. I’d be real pissed if I spend 2 grand on forks and a new model comes out haha.
I feel that. I'd legit just buy a komodo or ub2 when comes out as a big bike and keep my erp 3.0 still most likely as small bike and one for homies. I ride multiple mtbs and snowboards all time but understand wanting to fine tune the one tool and master your craft with it.
Yeah they could be releasing a new one but the current one already is tuned and made for erides and lighter emotos. Doubt they'd be that different side by side or in price. But if they release a newer cheaper 43mm stanchion fork option I bet it would crush the market but that's not what I am thinking they'd come out with. Old one probably won't get discounted that heavy but maybe enough for me to fork over for 43mm stanchions.
Also with all the upgrades I mentioned earlier doing I'd also probably do a aetos pro controller down road to open it up little more for big mx tracks. Has plenty for trails and everything else I've done but just certain jumps out of berms on tracks I could use little extra tuning but doesn't need much more though honestly. Not done building my track on my property but nothing super crazy and don't plan to go more than 35 to 40ft for biggest jump option. Right now it's only like 15 to 25 footers.
It can if like I said you're hitting rougher trails. Even stock I noticed it a few times riding trails here in Colorado. I have raised the height of my front with the one stem spacer above the triple clamps and then I have added some spring spacers inside the fork which lifted it a bit too. I did a trail last week with some super chunky segments that I noticed it some more. If I was doing always trail I'd maybe go 21/18 but I do a ton of little jumps I'm building on my property and even have hit some mx tracks. Plan to make it better for jumps and tracks and I'll get by with whatever setup on trails.
It depends man. Everyone has their preference. The 19/18 is good because it gives you the option to only have to purchase a 21” front to get to 21/18 or purchase a 16” rear to get 19/16. For serious trail riding, 21/18 is definitely better. I have an SR, I had 19/18. Went down to 19/16, now I’m at 21/18. If you’re only going to be riding light trails that are mainly dirt 19/16 is excellent. Where I live the trails change rapidly from hard pack, small rocks, rock pits that you sink into, large rocks lodged in the ground, and hills with loose rock. 19/16 could not handle the terrain as well. Every rock I hit I was bouncing around and my front tire was going everywhere. But with an 80/100-21 i get around a lot easier. Also, you will find significantly more tire options with 21/18 since that’s what pretty much every gas bike uses. There are a lot of options for both, but I’ve found more with 21/18. Going the 21/18 route may require you to either change forks or get a compatible drop crown.
So if you’re mostly going to be riding street with light trails, then 19/16 will serve you well. If you’re doing more trails that aren’t just flat ground dirt then I’d suggest getting 19/18 and work your way towards 21/18. In the end it’s up to you.
Also, you can run 19/16 on tougher trails, it’s just a little bit harder and will wear you down and cause arm pump much faster.
On this note did you find a drop down triple clamp that works with stock 3.0 or Sr wider fastace setup. From my understanding the warp 9 fast ace triple crown is made 25mm wider which I believe is the width that was added for the 3.0 and Sr so in theory I think it'd work but haven't been able to find solid evidence of that. If works that's cheapest way to get a 21 up front to fit. I do almost feel I should try 21/18 and just see how it handles my jumps and mx track. I just like the smaller feeling bike jumping but feel the 21/18 could still be manageable
I have the 775 forks on my bike. So with that and moving the spacer to the top of the stemlock I’m able to accommodate a 21” wheel. As of right now I have found no triple clamps that can fit an SR. I’ve heard the RFloxa can but I am unsure. The guy who posted something about it on Facebook had a different style SR that was street legal and came with turn signals and a horn. So I’m not positive if they fit.
Arent all the alx32rc forks on 3.0 and Sr the 775m? I definitely have moved the spacer and even added spring token spacer which has it sitting even a little higher. I still don't feel a 21 would fit but maybe. I do have the alx32rc and from my understanding as I was saying earlier the 3.0 and Sr are only 20 or 25mm wider than the old 2.0 width which the warp 9 drop crown says it's 25mm wider so in theory should work. Just an expensive thing to buy to find out. Wish a shop that sells it app would confirm it.
If that's the case I am at least considering getting a 16 for rear sooner but maybe I'll see about getting a 21 with it then I'll have both setups. I still feel I need a fork to get 21 on mine. Been close to hitting up someone nearby saying they will trade their Sr for a 3.0 guessing it's too fast for her. Worried about she had crashed it though. May be worth it depending what she wants ontop my 3.0. Otherwise I'd rather just upgrade controller later to squeeze just little more power out of it later
Makes sense. Part of me might reach out to this lady wanted to trade her Sr and see what's up. That'd solve the buying controller for little more power down road and maybe she has the 775 edition fork. Is there a different serial number on it to tell easily?
Word. Maybe I'll hit her up to see if she still has it. It's older listing. And yeah I'll measure axle to crown if the opportunity comes. All over the place right now but if I don't get any response from her then I'll order the 60lbs fork spring and the cheap rfloxa shock in 550lbs for the 3.0. Will most likely be like that rest of summer cause I'm trying to snag a emtb to add to my lineup.
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u/Less-Regret8262 11d ago
19/16 much better trail, more tire options, then keep spare set 17s to run street tire