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Post Info TOPIC: RAID AND ENDURO REAR SHOCK SIMULTANEOUS STRIP DOWN


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RAID AND ENDURO REAR SHOCK SIMULTANEOUS STRIP DOWN
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I'm a RAID owner with a standard rear shock unit that looked as though it had never been touched.  Given that my bike is a 1994 model, time for a strip down, clean and oil change etc.  I acquired an old standard rear enduro shock unit from ebay and decided to strip both units down simultaneously, so that any differences could be checked - although most seem to have been catalogued already.  The end goal was so refurbish the shock, plus swapping over the superior remote reservoir from the enduro model, which features adjustable compression damping.  This is not a step by step repair guide, since such a document already exists on this forum, courtesy of Brian and Steve.

20191126_205702_resized.jpg

 

So, to list the obvious differences. 

 

Raid model has a shorter spring in black as opposed to yellow.  I am yet to try and test the spring rates, but may find time to do this... using some dubious method.

20191126_205730_resized.jpg

 

Raid model has a slightly shorter shock cylinder, which I can only assume means this model has slightly less travel available.  The reduced overall shock length appears to be compensated for by a slightly longer mounting assembly at the bottom end.

Raid model has a different type of bushing at the upper mount, which appears to offer superior longevity - mine is perfectly in tact and functioning, the enduro is falling to bits.

Enduro model features a different oil hose linking to the remote reservoir, with banjo at one end only and straight screw in fitting with o ring on the other.  Raid has banjo both ends.

Raid model has a steel mount at the lower end, enduro is aluminium.

Remote reservoir is a completely different capacity, the enduro model being larger bore and featuring a rubber diaphragm and compression adjustment knob.  The raid model features a piston with an oring, in place of the diaphragm, and has no adjustability other than choice of ultimate gas pressure extending beyond 130 psi minimum.  The raid model is mounted on the bike with the gas side of the assembly facing the sky, enduro is the reverse.

20191129_205350_resized.jpg

Internally, I couldn't find any real differences, but didn't bother to take apart the shim stack assembly pf the enduro shim by shim, as others have already catalogued this information pretty well.

In terms of the work itself, I had a read of the step by step methodology document prepared by Steve and Brian, which has been on this forum for years.  There are a few things I did differently to make the job easier, such as taking off the oil hoses completely and draining some oil, before attempting to compress the remote end cap to get the hidden circlip off.  This enabled me to the job with just finger pressure on the raid, but the enduro still needed a gentle squeeze with a G-clamp.

I also took the whole shock assembly off the bike from the battery side, just so you can be sure it is possible.  Had to undo the entire exhaust however, so would probably go from the other side next time.

20191115_220224_resized.jpg

 

These are the parts laid out before cleaning.  I used gunk for most of it, as petrol smells inside part of my house... causes the lady to explode.

20191201_155717_resized.jpg

 

This is the reassembled piston with Sachs branded new seal head, new end cap and adding a bump stop.  This is a slightly deeper piston type than stock, so I hope it doesn't limit the travel of my shock.  The usual All Balls seal from the TTR shop was out of stock at the time I looked, which is why I sourced this.  Sachs is more expensive, but the new cap is a useful inclusion, as I find the originals tend to crumble a bit as you lever them off.

20191201_180442_resized.jpg

 

I have fitted everything back together and filled with Rock oil SVI 7.5, quite a thick oil as I believe I want more general stiffness....  but have come across a slight snag. 

The drilling and tapping of the remote reservoir cap to take a schrader valve, using a 7.3mm drill and 8 x 0.75 tap didn't work too well.  The threads bind increasingly as I tried to screw the valve into my newly tapped hole.  The reason for this would appear to be that the schrader valve thread is not actually quite that size of tap, but is just slightly off.  Schrader valve dims are apparently 7.747 x 32 TPI.  This requires a very special tap size 8v1-32, which only appears to be available to order from china.  This put a stop to the whole repair.  I tried two different brands of schrader valve from old inner tubes, but none would go all the way through my tapped hole.  I am going to have to counterbore half of the hole out at 9mm, then force the new valve all the way in with plenty of locktite to lubricate and seal the dodgy threads.  In truth the threads are extremely close, things should work out fine in the end. Steve and Brian did not appear to have this problem, which is odd / lucky.

I will follow up with some "strength" tests on the two springs and perhaps some notes on setting of the sag, if anything worth sharing is found.  The preload adjustment was at maximum when I took the unit off the bike, having never been adjusted by me to date...so we will see.  I weigh around 93Kg (pre christmas that is).

If anyone needs any further info to assist their own works, just let me know.  I have found this maintenance work to be straightforward so far, however I should point out that the shocks can simply be sent off in the UK for around £120 I think.  I don't know whether this price includes fitting a new seal head, but it seems good value for the time it will save you.  Personally I like to take things to bits myself, to get a better insight into the way they function...

 

9 December 2019 - post continued....

To continue where I left off, the dodgy threaded reservoir cap has been counterbored around 12mm, following which the valve squeezed through no problem, sealed with high strength loctite.  As an aside, I already owned a special schrader valve with BSP thread on the other side (suggested as a solution by one member)... however the version I own is a tapered thread type, which as far as a I know, should really be matched with a similarly tapered and threaded hole to achieve a gas tight seal - impossible to create (?) in the home workshop.  I therefore opted to make the standard schrader valve work, as this solution seemed neater to me, and less uncertain.

20191207_111708_resized.jpg20191207_112444_resized.jpg

 

 At this point I noticed another major difference between the original Raid shock and the enduro....there is no bleed valve on the Raid shock!  This was making it quite difficult to get the air out, so I decided to quickly pull things apart again and swap over the shock cylinders .....

20191207_115313_resized.jpg

 

The downside of the approach was the need to deal with the commonly faulty upper shock bearing on the enduro unit (which is a different rubberised type on the raid, that never seems to degrade).  So to remove the bearing, just one circlip was removed from one side and the bearing, which was then "tapped" out with a lump hammer.  I found no need to drill a hole into the shock body down one edge of the circlip to remove it, as per some instructions i found on this forum....a sharp screwdriver worked for me.

20191207_120548_resized.jpg

20191207_120636_resized.jpg

 

I now have the option of a slightly "bodged" but practical cost saving polybush, using the kit supplied in the TTR shop.  I'm not too keen on this method, since the intended "pivot" design at the end of the shock will be compromised, by becoming more of a fixed "moment" type connection.  Original yamaha parts are also available, at around twice the price of course.

I also have to consider powder coating the yellow spring (thanks for the pics Brian and Steve), since I now require the longer length Enduro spring version, having changed to the slightly longer shock body.   I need to use the bike soon, therefore timescales might affect the work i do at this point...

Somebody asked whether the Raid or the enduro shock is better.  The short answer is that the enduro version seems to be better, but only very slightly - the design is nearly identical.  There is compression adjustability on the enduro shock and there seems to be a slightly greater amount of shock travel, plus a bleed valve to help with maintenance. 

Both shocks were in fairly sound condition at the start, with no leaks being apparent.  The old oil that was removed from the raid was thinner than water and dark black, which means it probably wasn't functioning very well for damping purposes.

I am hoping to do some special spring "strength" tests shortly, comparing the black Raid spring with the slightly longer yellow enduro spring.  I'll let you know what happens....



-- Edited by thebertie on Monday 9th of December 2019 11:11:12 AM

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Good work Rob

We all love stuff like this and the bit about the bit about the lady exploding made me laugh!

Nice update about the thread of the schrader valve, not sure how/ why our one workedconfuseconfuse Maybe Bri can shed some light?

Just a question, did you not fancy doing the needle instead, thus saving the drilling and tapping? Always like some constructive feedback.

Cheers

Steve



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Hi Robert and thank you for posting the photos and information - very interesting and useful wink

I do recollect having a problem with the Schrader valve being very tight but I thought it was because I was too stingy to buy a 7.3mm drill especially to do the job and thinking that a 7mm would do just as well. Once drilled and trapped I couldn't go back and use the correct 7.3mm drill. I think I got around it using a method similar to your solution.

Your suggestion regarding the Schrader valve threads being different is a better explanation but adds a new twist regarding obtaining the taps from China unless Steve does a deal and offers them through the Totally TTRs shop. 

I have updated the guide (here) to include the correct tap and am very grateful for the correction - much appreciated!

Brian

PS I see the All Balls seal heads are back in stock - see here



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Hi Steve

I do own a needle kit, so could have gone down that route, but I liked the schrader valve idea for the ease of checking the pressure and adjusting in future.  I have made the bike bottom out on occassion, mostly by sitting down when I should have been standing up, but thought a bit more gas pressure might be helpful.  So...i want to mess around with the settings, the schrader valve helps a tiny bit.



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you can buy a schrader valve with the other end thread 1/8 bsp british standard pipe or gas same thread if that helps

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JOHNYBOY wrote:

you can buy a schrader valve with the other end thread 1/8 bsp british standard pipe or gas same thread if that helps


 that would be a very big and coarse thread for a bit of aluminium that is not very thick



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thebertie wrote:

Hi Steve

I do own a needle kit, so could have gone down that route, but I liked the schrader valve idea for the ease of checking the pressure and adjusting in future.  I have made the bike bottom out on occassion, mostly by sitting down when I should have been standing up, but thought a bit more gas pressure might be helpful.  So...i want to mess around with the settings, the schrader valve helps a tiny bit.


 Agree with that, as every time you use the needle you have to be so careful as it is easy to bend when pumping



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Can I ask why you just didn't rebuild the OE shock and go with that one Rob?

 



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Brian, i could have gone with the enduro shock,  but the yellow spring was a bit rusty and the bushing on the raid version was in better condition.  The raid shock body was in slightly nicer visual condition,  but in truth either shock would be functional after the refurb, i had an almost equal choice. 



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1/8 bsp is a fine thread not like 1/4 bsp coare thread

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thebertie wrote:

Brian, i could have gone with the enduro shock,  but the yellow spring was a bit rusty and the bushing on the raid version was in better condition.  The raid shock body was in slightly nicer visual condition,  but in truth either shock would be functional after the refurb, i had an almost equal choice. 


 Shock springs respond well to shotblasting and powder coating wink

The springs on the outside of the photo have been powder coated. The middle spring in original paint was included to show how good the colour match was biggrin

Springs powder coated.jpg



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Haven't seen a raid here  which shock is better and are they interchangeable 



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JOHNYBOY wrote:

1/8 bsp is a fine thread not like 1/4 bsp coare thread


 mis read it apologies John



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