|  | Topic : Rear hub needle bearing mod - Plan C |  |
| | | MotorMac | | Jupiter |  |  | | Reg. Date | : | 29/08/2010 | | Posts | : | 1,790 | | Location | : | Nor Cal, United States |
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| | Posted : 07 Aug 2022 - 02:12 Post title : Rear hub needle bearing mod - Plan C | | | Rear hub needle bearing failures, quick history:
Original 2010 rear hub assembly #T2010450 was replaced with Version 2 assembly #T201000636 at VIN #454618.
Change was to needle bearing under belt sprocket, replacing 37mm dia. x 24mm with a 35mm dia. x 25mm.
Mat1600's modification was to replace needle bearing with three 37mm dia. ball bearings and add a spacer (still looking for his post, but pics are available in his album - except this one=?).
Found 35mm dia. x 9mm ball bearings that are a near-perfect press fit into the Version 2 hub as-is. Mod is essentially the same as Mat's using three 35mm dia. bearings, source: Link (An alternative might be to use two 20x35x11 bearings from same source: Link )
Here are the actual 37mm x 9mm (V1 hub) and 35mm x 9mm bearings (V2 hub):
35mm bearings are a near-perfect press fit into my (failed) V2 hub after pressing needle bearing out. BTW, pressing that 35mm needle bearing out of the hub required a precise drift as only about 1mm of bearing edge is visible. Took a lot of pressure, too.
So, here's plan C. Top is factory setup, bottom is mod:
A spacer is required to make up for OEM inner race of original needle bearing - not sure if shortening the (failed) race is an option (as in drawing), or making a new one out of stainless might be best. I'm using Mat's 14.75mm dimension here, but it might end up being different and your results may vary. Found one post here from AleXL4 with yet a third set of needle bearing specs: Link
As in Mat's original modification, using three 9mm bearings will be 2mm too long, so circlip under RH seal will have to be left out - or, use two 9mm or 11mm bearings with a 2nd spacer between them. Will that circlip be missed? Is three bearings superior to two? I'm kinda leaning toward the two 20x35x11 bearings with a 3mm washer between them.....
Comments, suggestions, flaws welcome. Only wish Mat was here to weigh in.
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Previous related post: Link
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| | Post edited by MotorMac on 07 Aug 2022 - 17:43 |
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| | | Linkdog | | Thor | |  | | Reg. Date | : | 10/02/2011 | | Posts | : | 2,923 | | Location | : | Groveland, FL., United States |
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| | Posted : 07 Aug 2022 - 13:45 Post title : Re: Rear hub needle bearing mod - Plan C (Re: MotorMac) | | | You're on the right track. Could the machinist friend remove another 2mm from the bottom of the bearing recess to make the circlip fit? I remember Matt saying the 3 stack bearings would be about the same load rating as the needle bearing.
| Never drink from a cow with one udder! 2010 1600 Blue&White ( of course ) Long TORS and HP filter.
| | Post edited by Linkdog on 07 Aug 2022 - 13:46 |
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| | | MotorMac | | Jupiter | | | | Reg. Date | : | 29/08/2010 | | Posts | : | 1,790 | | Location | : | Nor Cal, United States |
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| | Posted : 07 Aug 2022 - 18:00 Post title : Re: Rear hub needle bearing mod - Plan C (Re: Linkdog) | | | Drawing isn't terribly accurate, Kevin - I've corrected it to show why there's no boring deeper: 2mm would take out what little material is at bottom of that bore. Between the radius from wheel bearing side and the stop (which is only 2mm dia. less than bore) there is precious little material. This is also what makes pressing out the old needle bearing so precarious.
I wonder where center of belt (stress) aligns with center of bearings, and if any offset there would matter.
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| | | Leethal | | Zeus | |  | | Reg. Date | : | 24/01/2011 | | Posts | : | 6,407 | | Location | : | Australia |
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| | Posted : 07 Aug 2022 - 22:39 Post title : Re: Rear hub needle bearing mod - Plan C (Re: MotorMac) | | | Would the balls in the 37mm bearing be better to handle wear and load than the 35mm ones?
I think Mat has an email address in his profile, try that. I will contact Gerry, he had a mate make a few conversions.
BTW, my Indian just uses one wide ball bearing, $212, but so far I have not seen any failure reports.
| Experience is something you get just after you needed it 
1600,Foran Razorbacks, Meerkat bypass, Dyno tune, real headlight,plenty of chrome,switchblade pegs, Hagon Nitro shocks & Ikon progressive fork springs etc. Scorpion Western Low handlebars. PH adjustable fork caps.
| | Post edited by Leethal on 07 Aug 2022 - 22:44 |
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| | | GerPa | | Jupiter | |  | | Reg. Date | : | 10/12/2011 | | Posts | : | 1,919 | | Location | : | Mackay, Central Queensland, Australia |
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| | Posted : 07 Aug 2022 - 23:43 Post title : Re: Rear hub needle bearing mod - Plan C (Re: MotorMac) | | | Link
Oih Motormac
Here is the link to ALEXL4 and the work he did on the Drive Hub Conversion,( Pretty much the same as Matts but just a little bit different in the machining. it was embedded in the Matt 1600 link on his upgrade. We have put alex conversion in a number of bike in this country including easyriders Superbird with no failures whatsoever.
Hope this helps.
Gerry D
| May-2011-1600, 20306 Tune, Mustang Vintage Solo Seat, Meerkat Cat Bypass, + Meerkat Modified Short TORS   ,K&N Air Cleaner,K&N Oil Filter, JBQ lifting system, Gold Plug Magnetic Sump Plug,Dart Fly screen, Rivco Risers, GiPro Gear Indicator, Breakaway Cruise Control, Avon ISO Grips, Scorpion Western Low Handlebars, Kury Switchblade Pegs, Garmin Zumo390LM,Michelin RC2 on Front RC 3 on ,Modified Rear Drive Pulley Hub Bearings (Mat1600/Alex4 Modification) Front Susp: Std & 7.5W Oil /126mm Air Gap & Rear:Hagon Nitro's with 26Kg/cm Springs + Lots of other "Bling" stuff.
| | Post edited by GerPa on 07 Aug 2022 - 23:46 |
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| | | MotorMac | | Jupiter | | | | Reg. Date | : | 29/08/2010 | | Posts | : | 1,790 | | Location | : | Nor Cal, United States |
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| | Posted : 08 Aug 2022 - 02:08 Post title : Re: Rear hub needle bearing mod - Plan C (Re: GerPa) | | | Greetings GerPa!
Yes, link to AleXL4 is in first post, above.
Version 1 hub, with 37mm dia. needle, will take Mat's 37mm trio (3 x 9mm = 27mm length) without boring.
Version 2 hub, with 35mm needle should take the 35mm trio w/o boring, too. These are the only hubs we'll see from now on.
Which begs the question, why go to 2mm smaller and 1mm longer needles in the first place? My V1 hub it replaced never had any issue.
Nothing to stop one from boring a V2 hub back to V1's 37mm. Glad to hear of your success! Especially if that circlip won't be missed.
(It should be noted that replacing either V1 or V2 OEM needle bearing is a non-starter; parts are not available, requires replacing entire hub assembly T2010636 (the V2).
Inner race of the 35mm ball bearing appears noticeably thinner than its 37mm cousin. Will that matter?
The 20x35x11mm version (x2 = 22mm L) should have more shoulder (and will fit under circlip).
Can three ball bearings handle the same load as a needle bearing? No.... so, what is the load from belt?
Otherwise, what, we replace the hub with every rear tire? Lots of chatter about all this on other sites, too.
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| | | Leethal | | Zeus | | | | Reg. Date | : | 24/01/2011 | | Posts | : | 6,407 | | Location | : | Australia |
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| | Posted : 08 Aug 2022 - 03:08 Post title : Re: Rear hub needle bearing mod - Plan C (Re: MotorMac) | | | Lots of chatter about all this on other sites, too
This is weird as I have not seen it hardly discussed on the three FB pages that I monitor. My own case is I replaced my original hub (updated 2011 year model) just for planned maintenance, not for failure. I think that was somewhere around the 100000km mark (it was still serviceable) and my current one has 76000kms on it with no issues. I don't understand why some are failing early, is it people sticking to the tight Triumph belt tension? I have never set mine at that spec.
Again FYI, the Indian belt tension spec is 34mm at 10lbs .
| Experience is something you get just after you needed it
1600,Foran Razorbacks, Meerkat bypass, Dyno tune, real headlight,plenty of chrome,switchblade pegs, Hagon Nitro shocks & Ikon progressive fork springs etc. Scorpion Western Low handlebars. PH adjustable fork caps.
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| | | MotorMac | | Jupiter | | | | Reg. Date | : | 29/08/2010 | | Posts | : | 1,790 | | Location | : | Nor Cal, United States |
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| | Posted : 08 Aug 2022 - 17:54 Post title : Re: Rear hub needle bearing mod - Plan C (Re: Leethal) | | | As Mat said early on, seal fails (as my first V2 hub did). Original V1 hub had no issues, problem started with V2 hub.
Complaints on this site go way back. Birdie heard the bearing noise, some blamed noise on belt chirp (quite different).
The RAT site has more than a few posts, some there refer back to Mat's fix here. I have no use for Facebook, not my thing.
It's not belt tension or alignment; I agree, Triumph's spec is too tight. Using 3/8" here (9.525mm). Shifting gets tight with less.
34mm is well over an inch. That's more like chain tension....
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| | | Leethal | | Zeus | | | | Reg. Date | : | 24/01/2011 | | Posts | : | 6,407 | | Location | : | Australia |
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| | Posted : 08 Aug 2022 - 22:17 Post title : Re: Rear hub needle bearing mod - Plan C (Re: MotorMac) | | | I realise that the discussion goes way back here, what I was referring to with FB (there are numbers there now, like there used to be here, like it or not) is the volume of old and new owners and the issue rarely comes up.
The 34 mm is a factory spec, it says something by not being tighter. I think your 3/8 is too tight (on or off the ground?), just my opinion and my experience.
| Experience is something you get just after you needed it
1600,Foran Razorbacks, Meerkat bypass, Dyno tune, real headlight,plenty of chrome,switchblade pegs, Hagon Nitro shocks & Ikon progressive fork springs etc. Scorpion Western Low handlebars. PH adjustable fork caps.
| | Post edited by Leethal on 08 Aug 2022 - 22:23 |
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| | | MotorMac | | Jupiter | | | | Reg. Date | : | 29/08/2010 | | Posts | : | 1,790 | | Location | : | Nor Cal, United States |
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| | Posted : 09 Aug 2022 - 20:56 Post title : Re: Rear hub needle bearing mod - Plan C (Re: Leethal) | | | Lee, you might well be correct, 3/8" (on side stand) might still be too tight, but that's where it's been all these years.
Recommended adjustment on HDs is 5/16" to 3/8" using same 10lbs pressure - or to twist belt 45-degrees, no more or less.
T-Bird has only 10 marks on belt guard spaced 1/8" apart, total = 1.25" (31.75mm) at max, suggesting it should be somewhere in the middle. I just don't think needle bearing is up to the task. Maybe the first version was.....
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| | | Leethal | | Zeus | | | | Reg. Date | : | 24/01/2011 | | Posts | : | 6,407 | | Location | : | Australia |
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| | Posted : 09 Aug 2022 - 22:03 Post title : Re: Rear hub needle bearing mod - Plan C (Re: MotorMac) | | | Mate who knows, I do remember that on a hot interstate ride many years ago I checked the belt tension and it was like a steel guitar string, this after a new rear tyre had been fitted at my dealer ( still under warranty then) , from then on I have let it run looser, approx 20mm. I rarely even put the gauge on it now, just check it like a chain. 
| Experience is something you get just after you needed it
1600,Foran Razorbacks, Meerkat bypass, Dyno tune, real headlight,plenty of chrome,switchblade pegs, Hagon Nitro shocks & Ikon progressive fork springs etc. Scorpion Western Low handlebars. PH adjustable fork caps.
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| | | MotorMac | | Jupiter | | | | Reg. Date | : | 29/08/2010 | | Posts | : | 1,790 | | Location | : | Nor Cal, United States |
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| | Posted : 11 Aug 2022 - 00:56 Post title : Re: Rear hub needle bearing mod - Plan C (Re: Leethal) | | | "Experience..." - one of my favorite quotes.
New bearings arrived in record time, so here's Plan D using two 20x35x11 bearings:
Note that inner race is more substantial than the 9mm bearings, at least at outer edges.
Here I'm adding length to spacer and a 3mm thick "outer ring" to aid with seating bearings. By placing bearings as far outboard as possible they will be nicely centered on sprocket/belt, much the same as OEM needle bearing was. I can install both circlips, too, unlike the 3-bearing mod. Think I'll give Plan D a try.
As for tension..... 20mm = .787 inch, over 3/4". (I kinda liked the HD belt twist method, except that I'm having no trouble twisting it 45-degrees as it sits here set to 3/8", so that's pretty much useless. I could probably twist it 90-degrees without much effort.) I'll try giving it 1/2" next time.
If you look at the photo I posted of my failed inner race, you'll notice all wear is on one side. That might be a clue... though one seal from needle bearing was completely detached and bearing was definitely contaminated.
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| | | Leethal | | Zeus | | | | Reg. Date | : | 24/01/2011 | | Posts | : | 6,407 | | Location | : | Australia |
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| | Posted : 11 Aug 2022 - 06:43 Post title : Re: Rear hub needle bearing mod - Plan C (Re: MotorMac) | | | Well it's certainly worth a go. There is probably some technical reason (thrust loads?) why the needle bearing has been used over the roller, but as I said Indian uses a roller bearing and they have worked well enough in wheels for decades. Also this way is easily and cheaply rebuildable. I still have my original hub and one day I will get around to doing the mod.
I wonder if mat1600 has bothered to or needed to do this to his Storm?
| Experience is something you get just after you needed it
1600,Foran Razorbacks, Meerkat bypass, Dyno tune, real headlight,plenty of chrome,switchblade pegs, Hagon Nitro shocks & Ikon progressive fork springs etc. Scorpion Western Low handlebars. PH adjustable fork caps.
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| | | Slcharger | | Jupiter | |  | | Reg. Date | : | 18/02/2016 | | Posts | : | 1,661 | | Location | : | Denmark |
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| | Posted : 11 Aug 2022 - 17:13 Post title : Re: Rear hub needle bearing mod - Plan C (Re: MotorMac) | | |
MotorMac wrote:
"Experience..." - one of my favorite quotes.
New bearings arrived in record time, so here's Plan D using two 20x35x11 bearings:
Note that inner race is more substantial than the 9mm bearings, at least at outer edges.
Here I'm adding length to spacer and a 3mm thick "outer ring" to aid with seating bearings. By placing bearings as far outboard as possible they will be nicely centered on sprocket/belt, much the same as OEM needle bearing was. I can install both circlips, too, unlike the 3-bearing mod. Think I'll give Plan D a try.
As for tension..... 20mm = .787 inch, over 3/4". (I kinda liked the HD belt twist method, except that I'm having no trouble twisting it 45-degrees as it sits here set to 3/8", so that's pretty much useless. I could probably twist it 90-degrees without much effort.) I'll try giving it 1/2" next time.
If you look at the photo I posted of my failed inner race, you'll notice all wear is on one side. That might be a clue... though one seal from needle bearing was completely detached and bearing was definitely contaminated. |
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I prefer this solution done by MotorMac. It is a similar solution to the modification i did with my conversion to wire wheels.
| Big Bird, Bordeaux with " Celtic theme " Airbrush, 2010, 1700CC, ABS, 65.000 km. Lowered with Nitros rear shocks, Linear front springs, Burchard forward footrest kit, Kuryakyn ISO grips, LOTS of chrome, SLcharger REV2+ tune, Modified Cee Baileys windshield, Oil pressure gauge, Air box elimination kit, Portet cylinderhead, Intake cam advanved 8 degree, Exhaust cam retarded 2 degree, 10.5 C/R, Knock sensor, Machined flywheel, DNA Chrome Spoke wheels, 18x8.5"- AVON AV72- 240/40/18, 21x3.5"- AVON AV71- 120/70/21, Corbin seat with backrest, 20W fork oil. Hiflo HF303RC oil filter, Penrite Racing 20-20W60 engine oil, Adjurl lights.
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| | | MotorMac | | Jupiter | | | | Reg. Date | : | 29/08/2010 | | Posts | : | 1,790 | | Location | : | Nor Cal, United States |
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| | Posted : 12 Aug 2022 - 03:10 Post title : Re: Rear hub needle bearing mod - Plan C (Re: Slcharger) | | | :-)
Best I can do for the "Outer Ring" above comes from HD in the form of an aluminum axle spacer that is - weirdly - 25mm ID:
(came from eBay, seems to be fairly common in various lengths.)
OD is about 38mm which means removing 3mm material to a hair under 35mm.
Desired length (thickness) = 3mm, actual = 3.175mm. That'll sand off.
= 25mm x ~35mm x 3mm - kinda like a big lock washer w/o the split.
Looks like spacer needs to match shape of OEM part, will cut it to length - if that's possible. Or make one in SS.
Torque on spindle is 110Nm (81 foot pounds) putting the squeeze on inner races....
They look rather delicate compared to that OEM spacer/race thingy, no?
Mat's 3-stack 37mm OD bearings have meatier inner races (photo above).
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| | | Leethal | | Zeus | | | | Reg. Date | : | 24/01/2011 | | Posts | : | 6,407 | | Location | : | Australia |
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| | Posted : 12 Aug 2022 - 06:44 Post title : Re: Rear hub needle bearing mod - Plan C (Re: MotorMac) | | | I would not be using aluminium if that spacer is in the torque area of the inner bearing races, it will get squashed. Not hard to make a steel one on the lathe.
| Experience is something you get just after you needed it
1600,Foran Razorbacks, Meerkat bypass, Dyno tune, real headlight,plenty of chrome,switchblade pegs, Hagon Nitro shocks & Ikon progressive fork springs etc. Scorpion Western Low handlebars. PH adjustable fork caps.
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| | | Linkdog | | Thor | | | | Reg. Date | : | 10/02/2011 | | Posts | : | 2,923 | | Location | : | Groveland, FL., United States |
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| | Posted : 12 Aug 2022 - 12:10 Post title : Re: Rear hub needle bearing mod - Plan C (Re: Leethal) | | | A 2nd. option would be is to make the 18.75 mm spacer to 15.75 mm and add a 3 mm spacer between the bearing " stack " on the inner races to help you find a size you would need. If you're having one made either one would work, but if you're looking for an off the shelf item I believe the 2nd. would be easier because you're only looking for the 20 mm dimension ( inside ) as opposed to the inner AND the outer.
| Never drink from a cow with one udder! 2010 1600 Blue&White ( of course ) Long TORS and HP filter.
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| | | MotorMac | | Jupiter | | | | Reg. Date | : | 29/08/2010 | | Posts | : | 1,790 | | Location | : | Nor Cal, United States |
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| | Posted : 12 Aug 2022 - 18:08 Post title : Re: Rear hub needle bearing mod - Plan C (Re: Linkdog) | | | Thought about putting a 3mm spacer between bearings, but doubt if there would be any advantage. All of these solutions, including Triumph's design, are slightly outboard from center of belt anyway.
Lee, the "outer ring" (to be made from HD axle spacer) isn't going on the spindle, it goes against outer race at bottom of bore.
It's the inner races that get squeezed by spindle nut torque. Compared to stock spacer/race, these ball bearings - all of them - look pretty wimpy and may be a weak point. That, and the difference in radial strength between ball and needle bearings. This might be a bad idea.
Best solution would be a single 20x35x25 roller bearing with 15.75mm spacer. Still looking but UTL so far.....
Found this $105US jewel for the V1 37mm hub (20x37x25): Link GerPa might like it....
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| | Post edited by MotorMac on 12 Aug 2022 - 18:50 |
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| | | Leethal | | Zeus | | | | Reg. Date | : | 24/01/2011 | | Posts | : | 6,407 | | Location | : | Australia |
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| | Posted : 12 Aug 2022 - 22:22 Post title : Re: Rear hub needle bearing mod - Plan C (Re: MotorMac) | | | Yep, understand, that's why I said "if", I didn't take the time to digest the info.
The one piece roller would be ideal, it's what Indian uses.
| Experience is something you get just after you needed it
1600,Foran Razorbacks, Meerkat bypass, Dyno tune, real headlight,plenty of chrome,switchblade pegs, Hagon Nitro shocks & Ikon progressive fork springs etc. Scorpion Western Low handlebars. PH adjustable fork caps.
| | Post edited by Leethal on 12 Aug 2022 - 22:22 |
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| | | MotorMac | | Jupiter | | | | Reg. Date | : | 29/08/2010 | | Posts | : | 1,790 | | Location | : | Nor Cal, United States |
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| | Posted : 13 Aug 2022 - 02:26 Post title : Re: Rear hub needle bearing mod - Plan C (Re: Leethal) | | | Found the ideal roller bearing for obsolete V1 37mm hub at Grainger Link
Not finding a 35mm version for the V2 hub (20x35x25). Not finding dimensions for Indian bearings, either.
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| | | Linkdog | | Thor | | | | Reg. Date | : | 10/02/2011 | | Posts | : | 2,923 | | Location | : | Groveland, FL., United States |
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| | Posted : 13 Aug 2022 - 14:20 Post title : Re: Rear hub needle bearing mod - Plan C (Re: MotorMac) | | | MotorMac wrote:
Thought about putting a 3mm spacer between bearings, but doubt if there would be any advantage. All of these solutions, including Triumph's design, are slightly outboard from center of belt anyway.
Lee, the "outer ring" (to be made from HD axle spacer) isn't going on the spindle, it goes against outer race at bottom of bore.
It's the inner races that get squeezed by spindle nut torque. Compared to stock spacer/race, these ball bearings - all of them - look pretty wimpy and may be a weak point. That, and the difference in radial strength between ball and needle bearings. This might be a bad idea.
Best solution would be a single 20x35x25 roller bearing with 15.75mm spacer. Still looking but UTL so far.....
Found this $105US jewel for the V1 37mm hub (20x37x25): Link GerPa might like it.... |
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True , but keep in mind that they are only supporting the cush drive. When you have to service the rear assy. and you will, the ball bearings are a lot easier to remove than the roller bearing, my original would not budge and had to use a dremel tool to grind the outer race paper thin to remove the preload.
| Never drink from a cow with one udder! 2010 1600 Blue&White ( of course ) Long TORS and HP filter.
| | Post edited by Linkdog on 13 Aug 2022 - 14:20 |
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| | | MotorMac | | Jupiter | | | | Reg. Date | : | 29/08/2010 | | Posts | : | 1,790 | | Location | : | Nor Cal, United States |
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| | Posted : 24 Aug 2022 - 19:10 Post title : Re: Rear hub needle bearing mod - Plan C (Re: Linkdog) | | | Continuing with Plan D hub modification (above), here is new spacer required to replace needle bearing inner race:
New spacer from dear friend/machinist in 220 stainless steel, left, stock (worn) 40.75mm, right.
Large diameter ends of both engages (inner) wheel bearing race, small end against new bearings.
Length arrived at by measuring length of stock race/spacer, minus bearings.
In this case, 40.75mm - 22mm (2 ball bearing Plan D) = 18.75mm. Note that Plan D also requires 3mm spacer against outer race(s) of new ball bearings (see drawings above in this thread).
Is this a good idea? We'll see how Ball bearings take the load versus stock needle bearing.
Plan C uses 3 bearings, Plan d uses 2. Ideal would be a single 20x37x25 roller bearing.
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| | | Leethal | | Zeus | | | | Reg. Date | : | 24/01/2011 | | Posts | : | 6,407 | | Location | : | Australia |
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| | Posted : 26 Aug 2022 - 02:32 Post title : Re: Rear hub needle bearing mod - Plan C (Re: MotorMac) | | | I'm kinda lost in all the threads but if three bearings have a greater contact area internally than two then I would assume three would last longer. Whether that is a concern in this application only the test pilot will find out.
| Experience is something you get just after you needed it
1600,Foran Razorbacks, Meerkat bypass, Dyno tune, real headlight,plenty of chrome,switchblade pegs, Hagon Nitro shocks & Ikon progressive fork springs etc. Scorpion Western Low handlebars. PH adjustable fork caps.
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| | | MotorMac | | Jupiter | | | | Reg. Date | : | 29/08/2010 | | Posts | : | 1,790 | | Location | : | Nor Cal, United States |
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| | Posted : 01 Sep 2022 - 00:32 Post title : Re: Rear hub needle bearing mod - Plan C (Re: Leethal) | | | I'll try a quick summary here. First thing to know is that there are two hub assemblies: V1 has a 37mm dia. bore. Replacement hub, V2, has a 35mm bore and 35mm dia. needle bearing. Both bores are 25mm deep.
Hardest part is pressing out old needle bearing. You'll need a precise 37mm dia. drift (V1 hub) or 35mm dia. drift (V2 hub) and a hydraulic press. There is very little bearing edge available, and it requires a lot of pressure.
If you're lucky enough to have a V1 hub with 37mm bore, make a spacer and use 20x37x25 roller bearing: Link Mat's mod used three 9mm ball bearings (37mm OD) and left out the last circlip (3 x 9mm = 27mm in 25mm deep bore).
The V2 35mm hub can also take three 9mm bearings (too long for circlip), or two 11mm ball bearings. Bore is 25mm deep, three 9mm bearings = 27mm (no circlip), two 11mm bearings = 22mm (circlip + 3mm left over). I added a 3mm outer ring.
If there is a 20x35x25mm roller bearing out there (I couldn't find one), use that instead of ball bearings - with a spacer. Spacer needs a big end against wheel bearing, small end against replacement bearing(s), length = OEM spacer/race minus bearings.
Question is, can ball bearings withstand the load? Roller and needle bearings have much more contact area than ball bearings do, better suited to this application. I expect to find out soon, as hub is ready to go.
Clear as mud, huh. One mistake I made: "Outer ring" has to clear spacer, so 25mm ID is too small. "Outer ring" is now 3mm thick, 3mm wide, 35mm OD, 29mm ID.
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| | | Leethal | | Zeus | | | | Reg. Date | : | 24/01/2011 | | Posts | : | 6,407 | | Location | : | Australia |
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| | Posted : 01 Sep 2022 - 20:43 Post title : Re: Rear hub needle bearing mod - Plan C (Re: MotorMac) | | | If you think the original 37mm bore version is better and don't have one, why not turn out a 35mm version to 37mm.
| Experience is something you get just after you needed it
1600,Foran Razorbacks, Meerkat bypass, Dyno tune, real headlight,plenty of chrome,switchblade pegs, Hagon Nitro shocks & Ikon progressive fork springs etc. Scorpion Western Low handlebars. PH adjustable fork caps.
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| | | MotorMac | | Jupiter | | | | Reg. Date | : | 29/08/2010 | | Posts | : | 1,790 | | Location | : | Nor Cal, United States |
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| | Posted : 04 Sep 2022 - 20:56 Post title : Re: Rear hub needle bearing mod - Plan C (Re: Leethal) | | | Would be helpful to know WHY Triumph made the change in the first place. Is OD the same and only the bore differs? Trying to avoid boring the hub, pressing out needle bearing is hard enough. But, this might all be academic anyway....
Left is my test subject, right is a factory-fresh replacement hub ready to install. Both include needle bearing inner race.
Here's the (new) problem: The end of stock inner race sticks out just past the circlip, about 1mm. I failed to notice that.
My two bearings + spacer exactly equal length of the stock inner race, which would move entire hub 2mm outboard (1mm past circlip + 1mm circlip itself). That, of course, destroys any hope of proper belt alignment. Say it with me: Duh!
Probably the entire reason why Mat left that circlip out of his 3-bearing stack, AND his 3-bearing setup would be 2mm past circlip.
Where it belongs.
So, bearing(s) have to total 27mm, 25mm (to the circlip) won't cut it.
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| | | Leethal | | Zeus | | | | Reg. Date | : | 24/01/2011 | | Posts | : | 6,407 | | Location | : | Australia |
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| | Posted : 05 Sep 2022 - 06:33 Post title : Re: Rear hub needle bearing mod - Plan C (Re: MotorMac) | | | Is it a problem? I have for years now aligned my belt by making sure everything is equal with the pulleys, in line with each other, and 20mm of slack or thereabouts. This gives me no issues at all. But, my belt is always to the right, so if your system puts the pulley further to the right by 2mm that would give me a nice gap. Not sure how yours sits though.
| Experience is something you get just after you needed it
1600,Foran Razorbacks, Meerkat bypass, Dyno tune, real headlight,plenty of chrome,switchblade pegs, Hagon Nitro shocks & Ikon progressive fork springs etc. Scorpion Western Low handlebars. PH adjustable fork caps.
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| | | MotorMac | | Jupiter | | | | Reg. Date | : | 29/08/2010 | | Posts | : | 1,790 | | Location | : | Nor Cal, United States |
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| | Posted : 05 Sep 2022 - 17:01 Post title : Re: Rear hub needle bearing mod - Plan C (Re: Leethal) | | | Hmmm, great point!
My belt likes right side, too. Have to give it an extra 1/4 turn to center, then it seems to go right side anyway.
Hmmm...
2 bearings w/circlip and take the 2mm, or 3 bearings w/o circlip.
Wouldn't 2 w/clip also change Cush drive location by 2mm?
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| | | Leethal | | Zeus | | | | Reg. Date | : | 24/01/2011 | | Posts | : | 6,407 | | Location | : | Australia |
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| | Posted : 05 Sep 2022 - 19:49 Post title : Re: Rear hub needle bearing mod - Plan C (Re: MotorMac) | | | It's not a tolerance fit so I doubt it would matter. I would fit the assembly and maybe do 500kms and pull the wheel and see what's going on.
| Experience is something you get just after you needed it
1600,Foran Razorbacks, Meerkat bypass, Dyno tune, real headlight,plenty of chrome,switchblade pegs, Hagon Nitro shocks & Ikon progressive fork springs etc. Scorpion Western Low handlebars. PH adjustable fork caps.
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| | | MotorMac | | Jupiter | | | | Reg. Date | : | 29/08/2010 | | Posts | : | 1,790 | | Location | : | Nor Cal, United States |
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| | Posted : 12 Sep 2022 - 04:00 Post title : Re: Rear hub needle bearing mod - Plan C (Re: Leethal) | | | If it wasn't such a PITA to change....
I'm all setup for 2 bearings, could switch to 3 by trimming spacer a bit, or scrap it and install the factory-new hub. May have to do something soon as hub that's on is singing that familiar tune again.
This site is getting rather sparse these days, huh.
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