Tapered roller bearing conversion

[old3]

Anyone done it?

I have 1060 miles on my new 300, felt the headset bearings clunking today and got in there to see what was up with grease before snugging it down.

Ball bearings? Seriously? WTF? Is it 1975 again?

So, anyone convert a Ninja 250 to tapered rollers yet?

[Motofool]

Nothing wrong with ball bearings for that application.

Here you have an article for the pre-gen 250:

http://faq.ninja250.org/wiki/Steerin...ng_replacement

[old3]

Alright, thank you! That will be going in the steering stem next time it is apart! Awesome.

[alex.s]

what's wrong with ball bearings? sounds more like the bearings are simply shot...

[old3]

The bike is a month old.

I ride pretty aggressively on some chattery, beat up mountain roads but they shouldn't be shot just yet. I'm guessing, like many other parts I've put a wrench to, (like the barely tight front brake caplier), they weren't snug at assembly.

All my previous bikes in the last decade or so have had tapered rollers in the steering head and I'll add them here too. The ball bearings work but are not the best choice. The contact surface alone is much greater on the rollers.

I'll add them when I do the Race Tech emulators over the winter if I keep this front end.

[old3]

All balls kit in hand, 3503 and 3504 bearings ready to drop in. Off to the garage!

[Alex]

Had this done on my 10R. It made a difference, however slight, in steering feel and smoothness.

[old3]

Wobble is gone, steering precision is WAY up!!!


Do this bearing replacement. It makes the bike feel so much more stable and smooth, no comparison to stock. Absolutely excellent mod.


Under $40 and 2 hours of slow paced wrenching start to finish.

[alex.s]

way up?... was there something wrong with your bearings before hand?

[old3]

Is it a new 300, they came loose at 1000 miles and the bike has always felt skittish, cheap and clacketty. I'm just off a 07 KTM 950SMR and a few more KTM 950s before that, along with a 09 530EXC supermoto wheeled street ripper. I feel it is a massive difference.

There was probably nothing "wrong" with the ball bearings and their races except they allow flex withing the steering head that you don't want and that you can, or should, be able to feel.

[old3]

Do it.

http://www.ninjette.org/forums/showthread.php?t=119551

[Alex]

/merged and moved to 300 tech area

[Surferboy120]

Thanks I ordered my bearings as well and will be doing this as soon as they arrive. I feel the exact same as you so if this can offer some improvement I am all for it.

[old3]

I put about 100 miles on it now, totally impressed with the results. Hitting expansion joints and frost heaves the bike just gobbles it up. It amazes me how bad it was stock.

[old3]

My son just cleared 1500 miles on his 2012 Ninja 250 and found his steering head bearings are shot too. Same hands off wobble at 50 MPH too. All Balls kit going in next week.

[choneofakind]

many many people get the hands off wobble at 50 mph. It goes away with new tires typically. Let us know how it goes. I'm curious to see how it works.

[old3]

Well, since we can rock his steering stem back and forth with an audible clunk, and feel it at the axle and the clamps, I doubt a new tire will do much to help it!

[choneofakind]

Hmmm, mine makes a little clunk when I walk along with it and tap the brake. Is that the clunk you mention? I noticed that over spring break and I'm wondering what to do about it.

Can you document your all-balls install a little this time so I can get a visual idea of what the process is?

They're only $20 a piece. I'd be in for doing the replacement as long as it's not too involved.

[old3]

A fellow here used some of my written guide and his pictures and comments to put it together nicely.

http://www.kawasa***************/for...-pictures.html

Worth doing, the bike gets super stable and solid feeling after this upgrade.

edit, I guess I can't link it??? It is a good guide if you can find it. I'll copy & paste my written stuff in a minute if I didn't do it here already...

[old3]

It is pretty straight forward. Jack up the bike, you need to have the wheel, forks and triples out so no race stand. I used a floor jack, a block of wood under the header and the side stand. You only need enough lift to get the wheel off.

Remove brake caliper, remove wheel, fender, handlebars, fork legs.

Remove upper center nut, then the lower retaining ring threaded on the stem, now the clamp will drop out the bottom so have a hand under to catch it.

Tap out the upper/lower races and toss the balls in the trash. Remove the lower race on the stem, a few taps with a drift and it pops off, real junk.

Install races by tapping them on the outer edge with a large socket, or you can use threaded rod and washers/nuts to "press" them in. This is the hardest part, cause you can't really swing a hammer much between the fairings up to the lower race. It took me 10-15 minutes of cursing to get that one in, it kept wanting to get crooked. A longer drift to tap and a second set of helper hands might have made it much easier.

Pack the bearings with waterproof grease, Bel Ray has great stuff, green in color at any bike shop, about $5 for a tub of it. You need to jam grease in the bearing everywhere, scrape it in by cupping your palm with grease in it and scraping the bearing thru it on the edges, spin the bearing and keep it up till you can't get anymore in it, them smear them on the rollers. Smear the races too. A heavy finger of grease.

Install lower bearing on stem, again, light tapping on the inner most edge so you don't trash the bearings. Use the 90 degree method with this and the races, move the point you tap 1/4 of the way from the last tap so it goes in straight.

Assemble the triples, you can tighten the upper ring till you feel the bearings get tight while turning the triples back & forth, then just slightly back it off to release the pressure. This is called seating the bearings, just like on a car wheel or trailer wheel.

Reassemble and ride it.

That Bel Ray grease is great for the axles too. Give them a swipe to cover them so they don't get corroded to the bearings in the wheels.


I think I hit all the big points. I'd use some red locktite on the caliper bolts too, or safety wire them.

Recheck the tension on the bearings after 500-1000 miles, you can just check for play by jacking up the front, grabbing the fork lowers and pulling them to check for play, (click, click) at the head.

[choneofakind]

Doesn't sound too bad.

Just to clarify, when testing for play, I need to pull/push the forks front to back and listen for clunks right?

I know play feels like on a bicycle. All I've done with those is tighten the stem nut a bit to make the problem go away permanently. I'll replace bearings with tapered rollers if I have to, but I want to make sure I actually have a problem first.

Anyway, if you could take a few pictures of the insides for me, that would be really helpful.

[old3]

That is the test, suspend the bike up front and have a friend shake the lower forks forward/back and put your finger at the edge of the top or bottom triple clamp & frame to feel for it too. If they got loose, they have probably been hammering and will have flat spots on them, making them no longer ball bearings...

You can also grab the front brake and rock the bike back & forth too, that may give you a click or clunk. Tightening them is a temporary fix at best.

I can't promise you pics as my son may do them without me, but that thread I can't link has a bunch of good ones.

[choneofakind]

Okay, I found a good link, that's to Geeker.

http://www.kawasaki_ninja_300.com/fo...-pictures.html
^remove the _'s. Thanks Alex for the quirky blocks

I should be perfectly able to do that. I'll go about that in the spring when I do my valve adjustment. Hopefully that's the last of my major work for the season.

[Mountain Dew]

Ball bearing steering bearings? After I read the OP I had the exact same reaction; seriously? What is this, 1974? I had ball bearings in my 74 CB550, and upgraded to tapered roller bearings and it made a WORLD of difference. I'm sure it's partially due to the race and balls being almost 40 years old, but still, almost every other sportbike has tapered roller bearings... Why did they decide to cheap out on the Ninjette?

[old3]

My buddies Aprilia Touno has caged ball bearing there, but the quality of those compared to these loose, un-caged balls is, I'm sure, night and day different. Lower grade steel and coatings will deform, not to mention the quality of the races too.

My son's bike is a 2012 with 1600 miles on it, same issue. He rides the same pocked up, beaten roads here in NJ/NY that I do. It takes me 4-5 years to deform a set of tapered head bearings on my MX bikes to where they get slightly notchy. I have a feeling the replacements will last 50,000 miles or more in a lil Ninja.

The added stability and solidity they bring the chassie up to is remarkable. I think that is a big part of the "frugal" feel of these bikes. That extra looseness that I guess many just accept or think is normal?

[alex.s]

did the bearing eliminate the frame flex while it's leaned over? if so, i'm in.

[old3]

I can't see how they wouldn't only improve the entire package. I have yet to get a ride in temps over 55f on the street, and no track time so I can't give a grade on any repeatable single curve or lean angle with textbook reliability. I'm also way off base from stock with shock and forks, but those are both stiffer and the frame feels like it was carved from billit at this point.

Of all the chassie mods I've done, GSXR shock, emulators, tires, the bearings were the biggest handling difference to the bike, followed a close second by the tires.

Mine were also fooked but I can't see how anyone's are actually good after the short miles our 2 bikes had when they were turned from round to square balls.

Just the increased contact areas of the tapered rollers should remove huge flex at the steering stem.

[choneofakind]

old3, I got my tapered rollers in the mail. I'll be doing them within the next few days. What size pipe did you use to tap the bottom one down? I see that it's schedule 80, but what diameter?

[old3]

I have a long, battered 3/8" drive extension I use as a drift for that. I work around the bearing with light taps. It went on with very little pressure. Just tap on the inner sleeve, not the outside or the rollers.

[choneofakind]

thanks for the advice. This is the first time I've messed with roller bearings, but my father has done them many times. He's given me the same advice you've mentioned. I'll let you know how it goes.

[Motofool]

Originally Posted by choneofakind

thanks for the advice. This is the first time I've messed with roller bearings..........

http://forums.ninja250.org/posting.p...&t=81770&tro=1

http://www.allballsracing.com/media/...stallation.pdf

http://faq.ninja250.org/wiki/Steerin...ng_replacement

[choneofakind]

I'm stuck. Getting the front end off was simple. Getting the triples off was also easy.

How do I get these darn races off? I've tried putting a screw driver on them and then beating the handle with a hammer. That didn't really work. Do I just bash harder? That's what the ninja250 wiki suggested... I still haven't tackled the race on the bottom triple either.

Help is welcome here. This is an area I'm definitely not an expert on.

[Motofool]

It is nothing more than metal and friction and you are an engineer, Chris

They may not have taught you this at school, but it is a good principle:

Big resistance requires big force.

[choneofakind]

Sooooo, basically, bash on it in one spot, then rotate 30 degrees and bash on it again. Lather rinse repeat. That's what I was suspecting.

Maybe I'll try some penetration spray like PB blaster to loosen it.

[old3]

Mine came apart with medium but sharp taps. Lube probably won't make a difference on these.

[choneofakind]

yeah, those suckers still aren't moving. Think I should go look into a bearing puller?

[Motofool]

Originally Posted by choneofakind

Sooooo, basically, bash on it in one spot, then rotate 30 degrees and bash on it again. Lather rinse repeat. That's what I was suspecting.

Maybe I'll try some penetration spray like PB blaster to loosen it.

http://www.dansmc.com/steering_bearings.htm

"To remove the lower bearing or bearing race, from the steering stem, simply pry the bearing or bearing race off with two screw drivers or a bearing puller or carefully use a chisel to pull the bearing off. The lower bearing/bearing race can be on VERY tight. Some heat with a hot air gun may help. To remove the top and bottom steering races from the frame neck, drive them out with a long drift and a hammer."

The trick is not generate a force that is in line with the tube.
There is no much room there for a bearing extractor.

If the thing is really bad, you could soak it with some ATF+acetone and then apply some torch to the tube, allowing to cool down before applyin force with two opposite and sharp screwdrivers and good leverage.

Wear eye protection, all bearing tracks or races can shatter !!!

[choneofakind]

Yeah I haven't even gotten there. I'm still working on getting the inner races out of the stem. I'll keep that in mind for when I get to the one that's stuck on the lower triple

EDIT: got the races in the frame.

[old3]

Nice!

[choneofakind]

I got it all figured out. Getting the new bearings in was a no brainer. I also got some riding time in. Keep in mind, I also installed a fork brace and cut proper length preload spacers to compensate for my springs being shorter than stock, so not all my results are due to the bearings.

My thoughts: I love the bearings. All my slop is gone and the bars are butter smooth. The difference is noticeable, but not earth-shattering. I think they were worth the time because I needed to service my bearings anyways, but I wouldn't swap for tapered bearings if it wasn't time for servicing. That said, the races were a major PITA on an old pregen. The bottom one was stuck in there badly.

Side note for you old3: I think the fork brace DOES make a difference. It makes the front end act a little more consistently over rough road, no matter if you're leaned over or not. There's not any sponge like there used to be. Again, I'm not sure if any of these results are due to one specific change or another, because I made 3 changes at once But I like my setup. In fact, I previously was worried that I'd have to play with fork oil weight, but I think it's pretty perfect as a street setup right now. I'm comfortable saying that I'm officially DONE working on the front end.