ISO DIY spring compressor

[HipGnosis]

I bought a used shock for my Ninja 650.

I want to cut the spring down a bit, so I need to disassemble it and so I need a spring compressor.

Anyone got a link to instructions to make one?  (that doesn't require welding)

Or can a rental tool be used?

[Cablebandit]

Your local parts store should have one you can borrow or rent.  It will most likely be much nicer and safer than anything you toss together yourself.

[Scratch33]

Refer to the duct tape thread.  

[HipGnosis]

Refer to the duct tape thread.  

[Castaway]

Do you literally want to cut the spring down, or replace the original with a shorter spring? Aside from length, the ends of springs are shaped so that they seat in the shock properly. Cutting the spring would destroy this fit, no?

[bomber]

Do you literally want to cut the spring down, or replace the original with a shorter spring? Aside from length, the ends of springs are shaped so that they seat in the shock properly. Cutting the spring would destroy this fit, no?

yes

[HipGnosis]

Do you literally want to cut the spring down, or replace the original with a shorter spring? Aside from length, the ends of springs are shaped so that they seat in the shock properly. Cutting the spring would destroy this fit, no?

I am going to cut the spring down.   There aren't any alternative springs (or shocks) for the Ninja 650s.  Cutting it down will raise the spring-rate and lower the bike.
I'll let ya know about the 'fit'.  I've been told I can duct-tape it in there.

[TuffguyF4i]

Just remeber that springs are not linear.  The k factor is based on many different voodoo style calculations of width, length, material, and otheres....

See those bouncy ricers in lowered civics and jettas?  That is from cut springs.  

[bisbonian]

I made a compressor out of 2x4 pieces of lumber.  The hard part was knowing how the shock came apart so I could make everything fit well.  

I made it so that it was sort of a box with a cutout on the top where the body of the shock needed to be pressed down to release the snap ring, the bottom of the box shape went under my floor jack so when I put the shock in there the bottom of the shock rested on the pad of the jack.  Pump the handle on the jack and the shock compressed.

You only need it to compress a small bit to get the snap ring out and this was easy.

I can take picutures of the fixture; I have no idea why I haven't thrown it on the fire yet.  Unfortunately I have no donor shock with which to demonstrate.

[JonS]

I bought a cheapo set from Harbor Freight. They have worked well for years.

[GTS_Rider]

I bought a cheapo set from Harbor Freight. They have worked well for years.

Thanks for that post. Just getting around to upgrading the spring on my MTS1200.  It actually is fine as it is riding solo with only a top-case and selecting two-up, with sidebags on the electro-gizmo suspension adjuster. Though if I'm 'actually' two-up with bags, eh, not so good. Lots of hard-bits have been dragged, giving a shower of sparks show for any rider behind...

Was just debating if I ship the whole shock out to have Ohlins USA install the spring for me, but checking the harbor freight option seems easy enough to do myself for probably cheaper than both ways shipping of the entire shock plus paying them for the 2 minutes it takes to install it for me...

Is this what you got?

http://www.harborfreight.com/macpherson-strut-spring-compressor-set-3980.html

[Andrew]

thats a mighty big spring compressor set up for the size of spring, sure it will fit??

[Pragmatic]

Ratcheting tie down straps.

YMMV and if you kill yourself don't blame me.