crf250 Rally

[garyboy]

Yeah .. I got a lot to learn about suspension.
Perhaps I will just drill holes and wind up the rear spring preload. to lower and firm up the rear?

The front has got more options .. firmer spring, extra spring, firmer oil, extra oil, cartridges, etc, ..

One fork lhs got damping oil, other fork rhs got a spring (with some oil)
I'll probably get an extra spring and new oil in one, lhs,
And firmer oil in the oem spring rhs.
I think?

[johnnyboxer]

Yeah .. I got a lot to learn about suspension.
Perhaps I will just drill holes and wind up the rear spring preload. to lower and firm up the rear?

The front has got more options .. firmer spring, extra spring, firmer oil, extra oil, cartridges, etc, ..

One fork lhs got damping oil, other fork rhs got a spring (with some oil)
I'll probably get an extra spring and new oil in one, lhs,
And firmer oil in the oem spring rhs.
I think?

Screwing down the rear shock spring, won’t make it ‘firmer’
All it will do is raise the ride height, so cancelling out lowering the linkage by drilling an extra hole in the bottom Clevis (which may compromise structural integrity)

[garyboy]

Why is it called Preload then?

[Seminole]

Gary I notice on the pic that the new holes are offset to the side a little, I think that is probably needed to avoid binding on the linkage. (havnt watched the video perhaps this is explained?)

I dont see a problem doing this, the steel u bracket looks quite meaty to me

[Seminole]

Why is it called Preload then?

I dont think JB explained that well, more preload will make the initial travel firmer, what it wont do is prevent bottoming out if your spring rate is too weak

edit you are thinking of going the other way though and reducing preload though of course giving more sag, but you are better off drilling the bracket and lowering it that way

[catcitrus]

All preload is is a compression of the spring that you can adjust. All it does is to determine the load at which THE SPRING STARTS TO COMPRESS. It does NOT change the rate(as long as its not one of those progressive springs where some coils go coil bound early leaving less coils in the system and therefore a higher rate (stiffer) than the spring with all coils "open". If you want to lower a bike then do it properly with internal spacers in the shock body and therefore not affecting preload when you set it up and mount the spring again--it just shortens the shock on full extension. Lowering links work to a point BUT can mess up the ratios on some bikes to a point that it ruins the linkage performance and the suspension action will suffer.

[Magnusson]

Why is it called Preload then?

Because it loads the spring prior to you sitting on the bike.

Spring rate stays the same (since the bike is too cheap to have progressive springs).

Suspension setup is fascinating, you have so many possible adjustments. Some adjustments working against each other, some complementing each other. Usually you want soft suspension at slow compression rate and stiff suspension at high compression rate. Depending on your surface you might want compression to be stiffer than the rebound.
As your shock compresses the air pressure inside rises. This will act as secondary spring. This secondary spring is always progressive. Putting more oil (less air) will make your secondary spring more progressive. Back when I was really playing around with this people would pump air into the shock to preload the secondary spring.
The changes in suspension forces acting on the shock because of lever/linkage changes as the suspension moves are also vital in suspension tuning.

[garyboy]

thank you all for your knowledgeable answers ... its beginning to get into me 'ed now

[garyboy]

maa noo tyree .. MT21 front ..

20220316_000643 (2) by gary boy, on Flickr

.. if its gone down by tomorrow ... i shall delete the pic ..

thems buzettis waz good

[Magnusson]

Sharing my experience.
The rear light on my rally didn't light up (breaklight worked) so I decided to do some diagnosing on this complicated machinery. After about an hour of hard work I had managed to fix it.
15 minute disassembly of the rear, removing the seat, top box, Camel tank, luggage rack, plastic cover (in this order) allowed me access to the bulb. Another 15 minutes cycling to the hardware store that according to their website had them in stock. Cycling back (cycling is hard). Installing the new bulb. Testing. Reassembling. Pat myself on the back for a job well done. After shortish test ride reward myself with cold brew. I'm the best boss I've ever had.
Why on earth isn't the rear light lens removable with couple of screws on the outside, like the old by bikes.

As a side note. Does anyone know of good LED replacement for 21/5w bulbs?