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RE: Rear Shock Woes
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I fitted the top bearing kit that is mentioned in FAQ once fitted it should be the last time you have to do it .

If it's just a tiny amount of oil fix up the bearing and ride .

If it's a lot it should be emptyed and refilled with the correct amount 



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I dunno if its easy to refill yourself.. I noticed the FAQ states to drill a hole in the shock to remove the circlip?

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TTRHead wrote:

Thanks mate. It didn't that long ago come back from a service. Gibbs Performance done it


Martin from Gibbs Performance rang a week or so ago asking about replacing the top bearing on a shock they had in for service/repair and I was able to help as we now stock them in our eShop.

Hopefully Justin and Martin at Gibbs can help future TTR owners by fitting them if needed whilst they have the shock in their workshop. The owner would still need to spread the mounting a tad to accommodate the wider bearing but that's an easy job and the bolts etc to do that come with the top bearing kit.

Brian

 



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Rear Shock Woes
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Just a small drill to make a spot where you can get under the circlip (I drilled in behind the clip and made a semi circle )  . Just knock the bearing away from the circlip first .

I have a screw driver ground down to a flat point that gets under the circlip they put up a fight but do come out 

Be patient an you will get it . 

And watch the clip when it does move they can end up in orbit . A bit of rag catches them 



-- Edited by ttboof on Sunday 5th of October 2014 10:25:36 PM

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Got e bearing out. Thanks for the help. Now shall I bother getting another original one or the one TTRfan has mentioned?

Can I put the oil in my shock or can any bike shop? or is this a specialist job?

 

Cheers guys..



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Well done!

If it helps you decide, retail for the new bearing is £47.26 plus, if you have damaged either of the collars, new ones are £10.97 each. Fowlers have the bearings in stock but not the collars. I think I have a couple of collars in stock if you need 'em.

To put oil in your shock you will need to release the pressure of the nitrogen first. After replenishing the oil, you would need to pressurise again with nitrogen so I would say that the job is definitely best left to a specialist. If I have any shocks needing attention I just send 'em off to Justin.

Brian



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Cheers mate. I think i'll go with the cheaper option then in that case. The stock bearing doesn't look up to much I don't want to keep having to change it!

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They are heaps better than the original and exelent directions online 



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I am posting my shock down to gibbs performance as we speak. Thanks for you help guys

i am guessing that the top of the shock on the TTR shouldnt move up and down when I have the bike on the stand and lift the bottom of the swing arm up and down?

it don't seem right to me having free play there



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"Excessive" play on the top or bottom shock bearings is an MOT failure and certainly won't help the handling wink

We have found MyHermes to be the cheapest courier for shipping shocks.

Brian



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TTRfan wrote:

"Excessive" play on the top or bottom shock bearings is an MOT failure and certainly won't help the handling wink

We have found MyHermes to be the cheapest courier for shipping shocks.

Brian


 

Cheers Brian. I just found royal Mail the dearest! £26!!!

i could of taken it to a local place near me but from what I have read on here Gibbs is the best place. Plus Justin is going to sort me a top bush

 

 

 



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We like MyHermes because we can drop off the parcel at a pick up point rather than having to hang around for a collection from home. Plus the drop off shop is near the Post Office so we try and do the two jobs together. 

Justin should certainly know his way around TTR shocks by now wink

Brian



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Does anyone know what make the rear shock is?



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No make names anywhere on them. Can only think they are made by or for Yamaha Japan specifically for the TTR250. I think that we are all agreed that no other shock will fit.

Brian



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RE: Rear Shock Spring Wt.
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i think you mean SPRING RATE vancor88 don't you?. actually i was wondering who makes TTR250 rear springs. we have a spring manufacturer here in Australia called KINGS SPRINGS and all their springs are exactly the same colour powdercoat as the TTR uses. might give them a ring and find out.

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RE: Rear Shock Oil
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Viene algun kit de reparacion para el monoshock?

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RE: Rear Shock Absorber - Q&A megathread
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Whilst looking at some photos of shock absorbers I came across this photo showing the infamous "clicker" mechanism in its constituent parts. There have been a couple of questions about it recently so hope the photo helps explain how it works wink

Shock lower adjuster showing clicker mechanism.jpg



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evileyeWe want Justin Gibbs to give forum members/totally ttr's buyers, a discount! I think you could earn a finders fee out of it Brian!....wink



-- Edited by peteBLUEttr on Thursday 30th of April 2015 11:50:55 PM

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I got a duff shock so that phone call might be sooner rather than later Pete!

My bro's TTR rear shock didn't so much start pogoing as went lifeless! There was only 3 clicks on the rebound adjuster which was also suspicious.

He was lucky enough to blag a good working shock on eBay so we did the swap and his old shock has been kicking about in my store waiting for attention. Today was that day!

I started off power washing it and it didn't look too bad underneath the crud.

I have a simple test for a shock which is to remove the spring and checking the damping action.

Dismantle shock1.JPG 

 

Compress the spring until there is enough room to pull out the slotted spring retainer:

Dismantle shock2.JPG 

This is what it all looks like dismantled:

 Dismantle shock3.JPG

At this point I pushed the shock together and there it stayed so no pressure in the system.

Dismantle shock4.JPG

This one will be soon on its way to Justin Gibbs for a rebuild.

Brian

 



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I have nearly finished stripping my Raid for spares and just got the shock out. A good time to compare it with an OE shock which I just happened to have been working on today biggrin

Raid v OE shock.JPG

 

The main differences are that there is no compression damping adjuster on the Raid reservoir and the bottom Raid yoke is steel rather than aluminium. 

The Raid's top shock bearing is a bonded rubber affair compared to the rose joint on the OE shock. That might be no bad thing as I haven't come across a Raid one with any play in yet.

The Raid spring is shorter but the yoke is longer such that, overall, the shocks are pretty much the same length.

Having tried them in different frames the two are interchangeable as far as I can make out.

Brian



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I am still struggling to find a sensibly priced bump stop for the 14mm diameter rod of the TTR's rear shock.

The other Yamaha offroad bikes (YZs and WRFs) use 16mm and 18mm rods so their bump stops won't fit snugly cry

Can anyone advise of a source please?

Brian



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Not got round to dropping mine into bikeworx yet squire, will let you know when i do..

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I popped into Bike Worx (now just The Worx as Jamie is doing cars as well) this morning to ask about getting some TTR bump stops and the guy I spoke to asked me to hang on whilst he priced them up. I spied that he was looking at the ORO catalogue so said not to worry as I have an account with them. I said I thought they might have a specialist supplier of shock parts but he said no. ORO's smallest bump stop ID is 16mm so I am baffled confuse

I will be interested to see how you get on!

Brian



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TTRfan wrote:

I popped into Bike Worx (now just The Worx as Jamie is doing cars as well) this morning to ask about getting some TTR bump stops and the guy I spoke to asked me to hang on whilst he priced them up. I spied that he was looking at the ORO catalogue so said not to worry as I have an account with them. I said I thought they might have a specialist supplier of shock parts but he said no. ORO's smallest bump stop ID is 16mm so I am baffled confuse

I will be interested to see how you get on!

Brian


 Oh...confuse



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Managed to source a supply of sensibly-priced bump stops - see here biggrinbiggrin

Have you taken yours in to Jamie yet Jason?

Brian

PS Really nice shock also now available - see here



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Rear shock
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Our rear shock on the raid has died, my brother has been trying to contact gibbs with no success so looking at other options as the mot is out and it's all it needs.

are all ttr shocks the same? There is one on eBay 

also has anyone had trouble sending or receiving shocks as I beleibe royal Mail won't touch them now as a mate lost a bicycle shock as they refused to send it 

 

 



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Hi there

Justin isn't brilliant on emails - best to phone - 01752 846888

The Raid and OE shocks are interchangeable and, because of the additional compression damping adjustment available, the OE shock is considered an upgrade. 

The shock on eBay appears to be missing its bump stop which isn't a good sign. The expensive bit is repairing the damper rod if it is worn or damaged.

We send rear shocks by MyHermes without any problems. Because they are pressurised with nitrogen they don't seem to be able to be sent by air freight.

There is a totally rebuilt one here that you can be sure is 100%

Brian



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RE: Rear Shock Absorber - which grade of oil?
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I have seen two different oils recommended for the rear shock, 2.5W and 10W.

Is there anyone on here good with suspension can say what should be used please? Also quantity needed assuming some spillage?

Brian



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TTRfan wrote:

I have seen two different oils recommended for the rear shock, 2.5W and 10W.

Is there anyone on here good with suspension can say what should be used please? Also quantity needed assuming some spillage?

Brian


Bump - any info please guys?

I think that, given the choice, I would go for the thinnest oil I could get.



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I am about to rebuild the shock on my 2005 TTR 250 so I read through this thread  for ideas.  I have rebuilt many YZ shocks, WP KTM shocks, and hundreds of FOX snowmobile shocks. 
To encourage home mechanics I can say for sure,  fix your shock and service it yourself before you spend money with suspension experts.

1. the big GORILLA  here is nitrogen pressure in the shock,  its absolutely unnecessary for riding a TTR 250.  Same as nitrogen vs air in your tires, every run straight air in your tires ?

2.  anything over 140 psi air or nitrogen in the shock after servicing  works great.  more pressure is a tuning variable,   220psi makes a stiffer acting shock, not good for most trail and road riders. In the TTR 250 shock the nitrogen or air is separated from the oil, so unlike old wives tales about  " YOU MUST USE NITROGEN "     back in the day when  nitrogen was  directly injected  into the oil like many of the  early gas shocks BILSTIEN shocks,  the theory was air would degrade the oil over time.  No so with the TTR 250 bladder/floating piston shocks.  Nitrogen's only advantage is, slightly more inert so heat swings affect pressure less and its cheap in a compressed bottle for MFG. to build shocks.

3.  most shocks have cheap oil stock and 5 years of use its for sure junk now, so service your shocks with new better sythetic shock oil.

4.  take care releasing any old gas pressure, then disassembly is simple and its disheartening to see how little is inside the shock, not much there and not much has changed in 30 years.

5. while servicing, might as well replace the seal.  The only seal replacement listed that I can find is  RACE TECH, about  $55 US.  While I have mine apart I will measure up the seal head to see if other cheaper seal heads from  ALL BALLS  will fit,  I don't think  ID x OD dimensions are that different, but overall seal len ght may differ and a spacer may me necessary if you used a different seal head.

6.  maybe hundreds of video's on U tube about shock rebuilding.  All apply to this simple old fashioned shock. So watch a video and redo your shock,  you really can't hurt it, on a 10 year old bike it really needs new oil. 

7.  FOR SURE        RACE TECH   GOLD VALVES  would make a big difference in how this shock works.  I just redid the valving on 2 KTM 200's and a 2004 KDX 200    with RACE TECH GOLD VALVES.    With in my trail riding group it prompted two KTM riders with 2016 machines to stepup and Gold Valve their suspensions as it was obvious that in one case a 16 years old bike now had way better suspension than their almost new $8k bikesl.





U

 



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I do the all ball ones here https://totallyttrs.com/epages/699105d9-e4cc-4b32-b236-84e72cd67f84.sf/en_GB/?ObjectID=2229803

Nice information Michael, very informative.

Steve



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Looking at the pictures of the Raid and OE / Bluey rear shock, if you run the Raid shock with the later bottom aluminium yoke, it would lower the bike some more??



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Hi Mike and many thanks for your helpful post. I am sure it will encourage owners to have a go themselves if they don’t have to find someone to pressurise their rebuilt shock with nitrogen.

I have a Fox bicycle shock pump which I think will provide sufficient pressure.

If not too late, any chance that you might take some photos of your TTR shock rebuild for us please?

 Steve and I intend to rebuild an OE shock using the seal head that he stocks. 

 What grade oil will you use please? Once you have done the deed, an idea as to the quantity would also be good to know.

 Brian



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Yes yes

Pictures and follow up info, pretty please



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I finally finished the rebuilt on my forks and shock on my ttr 250.  After reading many rave review on going 3" down on KTM enduro bikes,   I decided my 2" lowering for the TTr was out, might as well go 3", in my part of the world the saying is "    if your going to New York, no use getting off in Chicago "

 

SOME NUMBERS:  14 mm shock shaft diameter

                            46 mm shocky body id  so seal head is about  45.8 mm in diameter with an oil ring to seal it to the body

                            seal head is 21 mm thick.............somewhere out there are other seal head that could fit this,  thinner or thicker seal head would not be a problem

shock spring is   62 mm  ID

spring is  247 mm long

wire diameter and is straight wound  11.7 mm       so lots of other spring could work on this shock,  inside diameter is only thing critical, cut or make spacers for other spring lengths.

I will post putting it together 

                     

 

 

1. Removed the shock and cleaned it up with hot soapy water.  I found my shock to be in as new condition, confirming my suspisions that the TTR I bought has had mostly street use in a clean dry enviorment.

turned the spring adjuster nuts all the way down and that allows room to remove the spring keeper plate, and off comes the spring.

take out the screw in the end of the reservoir , grease up a hypodermic needle and insert through the rubber pellet at the bottom of the hole where the 4 mm screw was just removed. gas should come out, gas as in air/nitorgen

pull out your oild drain pan and over it take out the banjo bolt that holds the reservoir to the body and let oil drain out of the shock and reservoir.

put shock in vise with shaft up,  take a thin chisel and pry up the aluminum crud cap that fits in the shock above the seal, its just pressed in, doesn't unscrew, if you ruin it, throw it away, serves no purpose on an upside down shock.

take a punch and tap the seal head down, won't take much, down just far enough to allow you to take two small screw drivers and remove the wire snap ring that keep the seal from blowing out of the shock body.

clean this cavity with solvent, blow dry, and lube with grease or oil so the seal with come out easier,....... over your drain pan yank on the shock shaft and pull out the seal and rod.

clean every thing up spic and span,

shaft in vise end nut up, unscrew nut and set the parts out in order on a nice paper towel.                    If you drop all the parts, no panic, you need to know that;

 

To get the reservoir apart requires some care.  I use air pressure.   Shove down the aluminum end cap in the reservoir end, pull out the wire snap ring, clean the area and lube with oil or great,    take a great big towel and wrap this up and face a couple of inches from the back of your work bench, now shoot some air into the reservoir hose............i usually put the banjo fitting down on a piece of soft wood and blow air in the exposed side, careful you will be creating and explosion, some pop out...........uneventful, most come out with a lot of force and watch out  ITS CAN BE DANGEROUS.

the valve goes on one way,  close inspection you will see the valve holes different sizes,  when the shock rod goes down ( compression stroke) oil in a nano second has to flow through ALWAYS THE BIGGEST SET OF HOLES, in this case    FLOWING INTO THE OVAL HOLES,   so the opening for oil going into the oval holes is always towards the nut/bottom of the shock/bottom of shock hole.  THE BIGGEST SET OF VALVES always covers this biggest set of holes where the oil comes out, you will see that the valves seal against a flat surface around the oval holes,  SO OIL IN ONE SIDE/ SHIMS RESTRICT OIL COMING OUT THE BACK SIDE,    the valves are always a pyramid/ big valves (  all those thin flat washers ) biggest next to valve in descending order.   Valves/SHIMS can be identified by thickness .005-.015 inch and about 1.50 inch diameter down to barely bigger than the shaft they go over.

when you take apart  good motocross shocks some   SUSPENSION TUNERS HAS WORKED OVER,  you will find that the piston with the holes all over has had all the sharp edges smoothed where oil flows in,  in the case of      RACE TECH GOLD VALVING  you will get in the kit a new valve with radically smooth and improved oil flow bigger ports in the piston and options  and directions on how to build a shim stack out of the 100 or so new thinner shims that come in the kit, all to match your riding preferences.     SO while I was in here, I took a small rotary grinder  dremel tool in my shop with an 1/8  carbide pit and ported my shock piston like the big boys.  Picture that shows some of it,      oil flowing in   S M O O  T  H  the sharp corners, oil flowing out  DON'T TOUCH.

 



-- Edited by sledman 1 on Sunday 19th of November 2017 02:05:50 AM

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PUTTING THE SHOCK TOGETHER

1.   first  when I reassembled the shock shaft,  I pulled out two of the large diameter shims/washers on the compressions stack next to the valve.  My thinking was simply that as a compromise when Yamaha put these bikes together to cover all areas, when in doubt fudge on the side of stiff.  From my experience  too many washer and toooo stiff compression dampening in the stock setup, so I pulled a couple of compression washers.  On the rebound side,   my though is down the road, due to my being old and fat and excessive gear on my soon to build rack I may have to round up a stiffer shock spring, so I left the rebound stack alone because stiffer spring require more stiffer rebound dampening.

2. I put my new seal head on the shock shaft,  to make sure you don't damage the seal head o ring on reassembly, I put plastic sandwich bag over the threaded shaft end, greased it and the ID of the seal, and slid the seal head on with out any problems.   To figure how long a spacer I needed to lower my ride height 3", I had  used a  ratchet strap from frame to swing arm to suck my frame towards the ground until I had a 3" lower ride height,  my shock was  down .780 of an inch, so I had machined out a   .780  x  1.200  x  14mm id aluminum bushing to go on the shock shaft.  As my picture will show I also checked by odd washer bin and metal tube rack and found material that would also make a simple hacksaw only spacer, so I like lathe projects, but unnecessary, most of the suspension companies will send a nylon or plastic bushing when they send out their $75 shock shortening kits.  Pipe and washer will do fine, washer against the back side of the seal head.  So the spacer goes between the seal head and the big thick washer that is the start of the dampening stack.

3.  assemble the shock shaft,   make sure the foam bumper and crud seal are on the shaft, then the seal head, then the spacer you have built, then big thick washer and your valve stacks and piston,    thick washer/compression valve stack big washer towards rod end/piston with oval opening towards shaft end/rebound stack, tighten lock nut.

Put the shock body in vise open end up with the reservoir attached and zip tied to the shock body open end up,   fill 2/3  of shock body and reservoir with your favorite shock oil, add a little more oil,  then work your piston down into the oil and stroke it up and down  gently slowly watching bubbles escape, fill oil to with in 1" or so of top of shock and press the shock seal down past the ring groove...........oil should be coming out the top of the shock around the seal head making a complete mess, all good,  put in wire snap ring, pull up on shock shaft to seat at snap ring.

4.  Reassemble the reservoir.  The reservoir cap has the screw hole where we let out the gas.  In a home work shop the best setup is to drill out this screw hole and fit a schrader valve in the hole so you can air up your shock with a simple bicycle pumps or what ever.  I regularly inject nitrogen with a needle in these type of rebuilds. But here,  I drilled out the cap and installed a short shank schrader valve and will fill with good old mother earth air to  140 lbs.    So the pressure in the bladder from 120-250 psi lbs is just another  shock tuning variable.  Anything over 130 psi will allow the shock to function as designed. Many gas shocks use upwards of 300 psi.  The more pressure, stiffer the ride.  Play with it.  To drill and tap the cap,  note that the bladder slips right of this cap, making drilling and tapping easy.  So again, you want a mess , oil over the top as you install the bladder, go past the snap ring groove and put in the snap ring.

5.  To bleed out any of the remaining air, shock in vise with the bleed screw that is opposite the banjo fitting port for the reservoir, this screw out and highest point for shock, pump the shaft a couple of  mm  slowly working out bubbles, replace screw and move the shock around visualizing air bubbles rising towards this port,   remove screw and let out air if any , repeat until you have nothing but oil topping the screw hole, then screw it down.   Pump air into bladder as per your preference,  120-130 minimum.

 

If your have shortened  your shock in this process, now your spring may be toooo  long.   So its has to be cut down.  I will post a  a note on this.

 



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RE: Rear Shock Absorber - Q&A megathread FORKS ALSO
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I also rebuilt my forks with the intent to lower the front 3" as I have with the back of the bike.   I will post the fork set up where I saw a note about how far can you lower your bike.



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RE: Rear Shock Absorber - Q&A megathread
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That is a superb guide Michael - thank you very much for taking time out to share it with us - most appreciated biggrinbiggrinbiggrin

I think Steve and I are going to have to man up and set about replacing the seal head on his spare shock wink

Brian

PS Are you a professional motorcycle engineer Michael? You are very knowledgeable!!!!



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I am referring here to my two post about rebuilding my rear shock rebuild project    and   adding a spacer to reduce my ride height by  3".

 

the last issue to deal with is the standard spring is toooo   long to fit back on the shock with out using some kind of compression tool to install it.  A pain the the hindend.  

What I do is reduce the spring length by heating it while being compressed to the new spring length that I need to go back on the shock body, when enough heat is applied the spring softens and relaxes and you end up with  shorter spring.  I have also had success with using an abrasive cut off saw and in this case taking   3/4" of an inch out of the spring.  When you cut only ,you really don't have a nice spring end to seat back to the shock washers.  So, my preference is to squat the springs with heat. The goal is to heat the spring coil just above the finished end of the spring, heating until the coil simply relaxes down onto the adjacent coil.   I posted in the " MODIFICATIONS  HEADING "   of the forum my  fork rebuild for this same project and the process whereby I shortened my forK  springs.   In the case of the fork springs I heated the fork spring with a small propane torch and there was sufficient heat to soften and collapse the spring.   I tried the propane torch on the shock spring,    just not enough heat to get the job done, so I had to resort to using my  acetylene torch, just before you can see a little  red in the spring they quickly relax down onto the next coil.  Check out my pictures.  A blast of not that close yellow paint and job done.

 

So   with no special tools its possible to rebuild your shock,   remodel and improve your shock,  modify your shock for a more pleasant ride.   

 

Another issue that comes up is shock oil.  You have a beat up old bike and you're on a budget and you need a working shock.

1. you don't  need nitrogen,  air will work fine,   no air at all will just produce a softer ride.

2.  transmission fluid or  power steering fluid will work fine in shocks or forks.  Low budget, seal friendly, won't foam and a couple of dollars a bottle as opposed to bike shop quarts of synthetic shock oil for $30. I have regassed and changed fluids in probably hundreds of  FOX SNOWMOBILE SHOCKS  with  air and transmission fluid and fixed the seal head with a  .05 cent oil ring...........doing a set of 4 right now.  when you give  people the option of a fresh shock for $24 a piece with transmission fluid/power steering fluid or the deluxe version for $40 with shock oil and the same guarantee to work, most go with the low budget as good as fix for less money.

3.  I will dissect  a seal head when I have time from a TTR 250,  we might be able to cure a leaking seal head with just a good  VITRON  o  ring

 

the sequence of spring pictures is hopefully showing what  happens when I heated the rear spring and collapsed it down by  3/4" to go with my shorter shock in my bike lowering project.



-- Edited by sledman 1 on Monday 20th of November 2017 05:43:39 PM

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when I lowered the TTR 250 3"........kickstand blowout ?
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After completing my 3" front drop and rear shock 3" drop I was anticipating having to redo / shorten my kick stand.  What  a suprise when I took the bike down off its work table and back onto the garage floor and found out what had been a  sort of short kickstand and annoying  lean angle,   the new short 3" down bike gave me what I consider the ideal kickstand length and lean angle...........something had to be simple in this process.   On most of bikes I have modified with lower suspension, that last detail it the kickstand modification which was unnecessary in the TTr 250's situation.



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