Archive for the ‘SR500’ Tag

XS650: Fork Lowering   Leave a comment

Some time ago I posted ‘How to lower those Forks‘. Have always had misgivings about this method – it reduces the ammount of fork travel. OK if you dont push your bike.

It is true that our XS650s do suffer from posture. Front is a bit high/rear a bit low.

My blue rat runs an SR500 front drum brake. One of my SR500s runs with an XS650 fork.

Comparing the XS650 and SR500 upper yokes you can see marked differences. And similarities. Fork width and tube diameters are the same. Yoke height isnt. SR500 front sits lower as the yoke is flat.

unpainted SR500 upper yoke – painted XS650 one … (SR500 yoke has been a little modified-handlebar has been solid mounted and instrument cluster mounts have been removed) – apart from that the geometry matches


you can see that the XS650 yoke mounts higher than the SR500 – translates to the fork tubes sitting lower and the front higher


here you can see the same – the difference is about 27mm or so

Can definitely gain over an inch (ca 27mm) height change very easily without compromising fork travel.


Posted July 15, 2015 by xscafe in Frame - Forks

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XS650: SR500, Velorex Sidecar   1 comment

Once upon a time I had this nice little SR500.

my 48T SR500


I got it into my head to build a sidecar – to take my son to school. Started collecting bits. And ideas. (I did consider using the XS650. Decided against it as the SR and the Velorex match pretty well. Both light and manouverable.)


making a start … leading link forks, box section swingarm and front disc brake … ended up reworking the forks – added an extra 1cm castor (nachlauf)


Got hold of a Velorex 562 sidecar. How to connect? Collected a lot of ideas.

  • Original Velorex frame clamps. Too much point load on the frame. And they work loose.
  • Mount points welded directly to frame. Weakens frame. Point loading.
  • Subframe. Bolts directly to frame. Sidecar mounted to subframe. Load distributed. Solid.

Sounded good to me. What about TÜV (MOT) certification? Could make my own subframe but I’m not a ticketed welder. Visited my local friendly greycoat (TÜVler). Fixed his brown-eye on me and shat on my ideas. Some people simply have no imagination. No sense of adventure.

Found a list of Gespannbauers (sidecar builders). Rang around. Karl Schmid from Mickhausen near Augsburg was the most approachable, and fitted into my time frame. So, off I went. Beginning of September. Said he would try to have it ready by the end of the month. OK by me. Spent the next week constructing at Automechanika – Automobile industry Trade Fair. Stand handover Monday. Home late. Phone rings 08.00 Tuesday morning “TÜV is on Friday. You can pick it up then.” Hang-on? It’s not even midmonth! I’m not ready! Cant believe it’s early. Kool!!

Commitments, illness, work, rugby meant I wasn’t able to get down there for a week. Got a train ticket, €39 to Schwabmünchen. Left Frankfurt at 05.30. 20 minutes late. By Stuttgart the train was getting pretty full. Ah, yes, 1st day of Oktoberfest. God I love girls in Dirndls. Nothing quite like it. Eye candy.

Was picked-up at the station. Sweet.


finally there


half workshop half house … nice


Smells just like a metal workshop should.

Karl Schmid: Gespannbauer


there she is … waiting


Took my time getting home. 650km. The first 3 hours in driving rain. Forgot to switch back from reserve and ran out of gas in the middle of nowhere. Great way to meet friendly strangers. Took the sideroads. No map. Using the sun position – when I could see it. And geography. Had a great day. Perfect way to meet my new toy. Glad I took 3 pairs of riding gloves. Meant dry warm hands. Mostly. Uses more gas, be careful cornering, no need to put your foot down when stopped.


front on


rhs … the boat is sitting on the original frame podests … it is possible to rework these and lower the body 30-40 mm … lower centre of gravity … adding an MZ torsion bar (bike swingarm to sidecar swingarm) helps handling too


you can see the body mount podests on this frame


as a reference: this velorex frame has been heavily modified – cross bracing, lowered body mounts, bolt on lower frame mount points, extended rear, self-made shock tower, self-made extended swingarm


lhs … have some longer konis I may swap into the forks – lift the front a little


324mm konis up front, from my guzzi … replace the series SR shock 316mm … feels better


connected – front view … exhaust pipe is very close to the lower car mount – i have now ground the mount to give more free space for the pipe


connected – rear view … the lower rear sidecar mount, seen here has been shifted to the rear of the sidecar to leave space to kickstart … the upper rear mount is just on the limit of being restrictive, my boot heel hits the bar if Im not careful


front – upper … boxed over the frame


front – lower … bolted to the front engine mount


rear upper, subframe fixed to the shock mount, sidecar mounted off the subframe … you can see the lower sidecar mount point going off to the left … rear lower subframe mount uses the footpeg mounting points (will take photos of these and post as well)


right hand rider footpeg now welded directly to the subframe … subframe mount uses the frame points previously used by the footpeg


sidecar brake cable … attached to footbrake rod – pulls against the alu block


brake cable mounted to the swingarm shock mount


nice bonus – the front lower sidecar mount serves as a perfect footrest – very comfortable riding – need to practice braking with my heel


Fully certified (TÜV)!!

Now I’m ready to take my 6yo son to school.

off to school


I’ve now ridden this a couple of thousand km. Not bad for a month.

  • Have added a longer set of shocks to the forks-a bit more height (not too much)-needed to alter the sidecar settings slightly.
  • The rear shocks are far too weak. Tried a set of SR500 konis – still too weak. Looking for a better solution.
  • In retrospect I might design the subframe somewhat differently. As a 1 piece there is structural integrity and load-spread across the whole frame but the thing will need to be removed to repair things like clutch, kickstart, oil pump. A 2 piece subframe, although loading the front and rear of the frame separately allows access to the right hand case. Just how strong is the original frame?
  • I will add a rollbar and 4 point seatbelt.
  • Am glad I didn’t use the XS650. The Velorex is light and flies easily. Great for freaking out cagers that follow too close.
  • Had forgotten just how physical sidecar riding is. Body position is critical when racing through corners. My 6 yo son is becoming a good monkey.

Couple of updates …


VM32SS carb from an early XT500, rejetted … large increase in torque for minor loss of top speed (-10kmh max.) … purrfect fit … have ordered a new boot


Have exchanged the carb. Taken the BST34 flat slide out. Put a VM32SS round slide from an early XT500 in. Direct fit. Mates to both the carb boot and air filter

no problem.

Starting point : 41mm single wall head pipe … K & N filter insert, open carb boot.

  • Pilot Jet 25
  • Main Jet 260
  • Needle Clip position #4
  • Float at 21mm (float was twisted-one side sat higher than the other)
  • Cables are different, (both 2 cable system) … shortened the BST push cable outer and used it as a VM pull cable, added a second nut to give myself adjustment at both the carb and handlebar.

I love the difference. Not quite as much top speed (I rarely travel more than 100-105kmh anyway) BUT there is a noticeable increase in torque from idle. Pulls great through the complete rev range. Fuel consumption is better too.

Exchanged the std Velorex lights for LEDs. Figured it would be easier on the batteryless electrics I run. Had halogen blinkers on the left hand side. Load-independant blinker relay. Seems to work with halogen front and LED rear but not halogen left and LED right. Appears to require the same combined load on both sides. Swapped the halogens for LEDs and all was well. Except for the headlight the bike now has LEDs all round.


LED rear


and LED front


Have booked the bike in to have the subframe modified. Never liked the front top mount – headstock. Transfers the stress directly to a known weak point. The square section tube under the oil tank. Cracks along the weld – both sides.


subframe top monut, front … at headstock … clamped to known weak point – leads to cracking along the welds


Had a front brace made up. Clamps to the frame. Bolted up through the steering head – 2 bearings keep the steering operating. Brace back to the subframe.


brace from the rhs … can see the frame clamp, the bearing housing under the steering head – there is a bolt through this from below attaching it to a block inserted into the lower yoke (this is held in place with the bolt coming down through the top – could also have been cemented in place)




front brace – rhs – showing link to subframe – note, this is all easily removeable, clamp releases, link unbolts from brace, brace separates from bearing house


my other three-wheeler … shop hack … sharing space with the XS

A common SR500 rear wheel problem is the wearing out of the rear sprocket carrier. If this isnt regularly greased via the provided grease nipple the wear accelerates. Result? Sloppy rear wheel. The added stresses imparted by running a sidecar exacerbates this problem.

This can be rectified by machining the carrier  ID to fit 1 or 2 bearings and reducing the existing stem in the hub. I tried contacting an SR500 forum member here in Germany but he never replied. A pity as he provided a nice 2 bearing modification. While looking for a solution I found complete a rear wheel, already modified, on fleabay. New bearings, brake shoes, carrier dampening rubbers. For cheaper than used wheels usually go for. Score!

complete rear wheel – already modified – single carrier bearing and reducing spacer


rear sprocket carrier – machined to fit a bearing – reducing spacer fitted – i have covered this with the plastic cover found on XT500s – lube as normal using the grease nipple provided


rear view of sprocket carrier – can see both the bearing and reducing spacer … fits as normal to the hub


XS650: K&J Swingarm   Leave a comment

Been busy lately. Summer (well not really much of one) riding. Work. And, best of all, play.

Our son turned 6. School. Need to get him there and pick him up. Started a while ago collecting bits to turn my SR500 into a sidecar. Velorex 562. Leading link forks. Box section swingarm. Steering damper. Better shocks. May yet even add a battery. Had a subframe made up – bolts directly to the frame. 4 point sidecar connection bolts to this – no welding to the frame – better load distribution. Easier to get certified.

Got a K&J box-section swingarm for a price I couldn’t refuse. Included all the bolts, bearings, axles … ca 5.7kg.


k&j box-section swingarm … shock mount bolts, axles and chain tensioners  not shown


Checked the existing bearings – OK. But the bearing races showed definite wear marks where the rollers have contacted. No internal spacer!! Checked their website. This is standard-no spacer. Means the bearings take all axial load. Anyone who has left the internal spacer out of their wheel when replacing bearings soon learns not to do this. Their instructions say to tighten the swingarm pivot to the point that the swingarm slowly lowers itself from a raised position. Fully loaded bearings – no wonder the races are marked. New bearings.

Measured it up. Figured there was 164.5mm space between the bearing centres. 16mm internal diameter. 22mm OD would fit inside the bearing cages. Cut myself a bit of pipe. Fitted it – too long – too much play. Remove. File. Refit. Did this 3 times before I got the fit I wanted. Now, there is no sideplay and the swingarm can move freely.


spacer … 164.5mm long …. 16mm ID … to the left is one of the bearing carriers, greased, ready for installation


Next problem. No chain-rub protector and the pivot tube has a larger OD than the original. Had a polyeurethane bread board the wife wont miss. Grabbed my holesaws and cut myself a new rub protector.

Mounted the chain guard. Shock mount bolt is in the way.


shock mount bolt blocking the chainguard


A bit of violent grinding soon fixed that.

For some reason K&J decided to reinvent the wheel. Put the brake plate anchor topside. Original is underneath. Must rotate the plate. The brake actuation geometry is now all fucked up. Bright. On researching they fixed this later – gave the choice of over or under. Later models are fitted for the original anchor. This didnt help me. Made myself a new anchor. A comprimise, but helps.

External dimensions of this swingarm are slightly larger than original – means the brake rod runs real close. A little judicious bending solved this. Also took the time to remove the brakearm pivot. Like the XS650, the SR500 has no grease nipple here and people forget to regularly repack it. Tends to seize when least desired. Fucking Murphy!!


brake arm pivot – getting a bit dry … caught just in time


Things to do:

  • Dechrome the swingarm – i hate chrome just as much as i do policemen
  • reposition the brake plate anchor
  • powdercoat it black
  • replace the missing grease nipple – swingarm pivot shaft
  • keep riding

If you’re wondering why I’m writing this, you may not have figured out that the SR500 and XS650 swingarms have the same pivot dimensions.

Posted August 31, 2012 by xscafe in Frame - Handling, SR500

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XS650: Jacket   Leave a comment

… kool jacket …

.. for liebhaber …

… currently on german ebay … until May 20, 20:05

Posted May 15, 2012 by xscafe in Frame - Design

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XS650: SR500 Rear Wheel Bearing Spacer   Leave a comment

I need one. A bearing spacer. Rear wheel. SR500. Drum brake.

Goes inside the hub. Between the bearings.

If anyone has a spare one handy please drop me a line – reply below.

Seems the drum and disc brake versions are different:



Drum Brake (spoke/mag)



Disc Brake    (mag)



drum brake rear wheel bearing spacer (XS650)


This is from an XS650, but you get the idea.

Thanxs …

Rear Wheel Bearing Spacer


mag/spoke: drum  #275-25317-00


mag/spoke: drum #90560-20135










Ring OD:



Posted December 7, 2011 by xscafe in Frame - Wheels, SR500

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XS650: Other Manuals   Leave a comment

Got a lot of use out of these too…

SRX6 Workshop Manual

SRX600 Owners manual


Yamaha XT500 SR500 Service Manual

Posted April 20, 2011 by xscafe in Manual - Workshop

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XS650: Fork Brace   3 comments

I have a wife and kids. A home. Some toys. And my bikes. We live ok, are not well-off. Cash is always tight. Whatever I buy for my bikes is a compromise. That cash could, simply put, be used for other things.

So. Bang for my buck?

Good question.

I have an answer. It’s not a single item however.

There is a list. Needs prioritising according to your pocket and your bike.

If it’s not broken don’t fix it.

My basic list includes:

  • tapered roller steering head bearings…if needed
  • new fork oil, and seals when needed
  • swing arm roller bearings or bushes…always needed
  • rear shocks…anything is an improvement
  • check wheel bearings
  • look at the tyres
  • fork brace

Note that none of these are related to the motor. All affect handling. Directly.

I always keep my eye out for cheap fork braces. You hardly ever buy a bike with one on it.

Basic pattern is:

  • 35 x 55 x 185…’77-on
  • 35 x 55-58 x 185…’76
  • 34 x …………………….up to ’75 -i don’t have one here to measure

The later 35 x 55 x 185 version is shared with several other models. Some are:

  • SR500
  • XS750
  • XS1100
  • XJ550..80
  • XZ550S..82
  • XJ400..82
  • XZ400..82

’76 models are also found in ’80 Suzuki CM400L

The 35mm models produced that I know of are:

Daytona..japan..i have these…i like the foil shape, although i turn it around, to push down as i go forward


motoline … 35 x 55 x 182-185 … forged .. 500g


Motoline – certified for:

Yamaha XS 500 650 750 SR 500 XJ 550 XJ 650  XS 400 TR1

Kawasaki KZ650B KZ750E KZ750B Z1F KZT00A KZ550B KZ440A

Suzuki GS400 GS1000 GS850 GS450

Honda CB400T CX500 CB1 CB750F CB750G

Tarozzi…can fit the boot or gaitors over these


Telefix…also boot and gaitor friendly


AME…simple, clean


and the old standby .. hooped


Any of these will strengthen up the front. Remove the fork flex. The results are immediately noticeable. Careful, it will uncover other problems.

Where do you stop?

Posted January 19, 2011 by xscafe in Frame - Forks, Frame - Handling

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