Suspension 1980 Honda CR125 DoctorDanger.com

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>The suspension of our Project CR125

If you've been following the rebuild you'll know that the front forks were deeply pitted with rust and the rear shocks had less dampening than a whoopee cushion.

We started by dismantling the forks and getting the fork legs rechromed by Dynasurf in Sandbach (01270 793032) and ordering new fork seals...

Meaty, beaty, big and bouncy...forks

	Dismantling the forks was easy, just undo the fork tops (not easy) and then drain the fluid and remove the allen bolt from the bottom of the forks. The damper rod and fork leg then simply pull out. Having cleaned up all the parts we set set about rebuilding the forks. Begin by inserting the washer (comes with the fork seal from Honda) into the top of the fork slider...
	Next in is the actual fork seal, which is still available from Honda dealers and is a fairly chunky seal...
	To get the fork seal in you'll need to drive it with an appropriately sized socket, we used the old seal to get it started, and covered the new seal with a rag to avoid damaging it. The seal has to be driven right down into the slider, you'll know when its fully seated as the washer underneath will stop rattling.
	Another washer and the circlip are then inserted to retain the seal. The dust seal then goes in on top of these - unfortunately these are virtually impossible to get as they are a strange size - everyone we rang from Honda dealers to specialist oil seal suppliers said you won't get one...so we reused the old seals and fitted some gaiters to the finished fork...
	Having done the seals you should then insert the cap for the end of the damper road, with the machined end facing the bottom of the slider as shown
	Now you can insert the fork legs, make sure that the bush that clips to the end of the fork leg has been reinstalled (it needs to be removed for rechroming). The fork leg should slide in fairly easily, but try to avoid forcing it in as this may damage the new seals - use a little WD40 to make sure it slides easily.
	Now for the only tricky bit...the spring is actually retained on the damper rod, and it is a bit of a faff to get the spring back on the damper rod, under compression, and to screw the fork cap back on
	This is what you should end up with, note that the bolt on the top of the damper rod should be tightened to the base of the fork cap to stop the damper rod working loose from the cap. Also note that there is a washer that sits between the spring and the bottom part of the damper rod assembly.
	Note that our damper rods were so badly corroded that they wouldn't move when removed, so we soaked them in de-rusting solution and then gave them a quick rubdown with emery cloth...Next, the whole damper rod/spring/cap assembly is fed into the fork leg and slider - easy, unless you haven't removed the cap from the end of the damper rod as this won't fit through the inside of the fork and needs to be inserted before the fork leg (see above). Once the damper rod assembly is in you need to insert the allen bolt into the bottom of the slider. This bolts the bottom of the damper rod to the slider and needs to be tightened before filling up the fork leg with oil, as does the drain plug on the back of the slider - we forgot this and wondered why all the oil we poured in ended up all over our feet...dohhhh.
	Filling the forks with oil was relatively straight forward, although we couldn't get it all in without pumping the fork slightly, we think this is because the hole in to the top of the damper rod was still a bit tight due to corrosion and by compressing the fork slightly you allow the fluid to flow in a bit more easily. Each leg takes around 300ml of fork oil. We used 10w oil as we are fat - the Honda and clymer manuals we have state different amounts of fork oil, so we'll see how they work before we recommend a definite quantity.
	Having screwed the caps down into the legs (make sure you don't snag the O ring seals) you can then put the forks into the bike. Get the forks level and then tighten up one of the pinch bolts in the bottom yoke.
	Before tightening up the whole assembly fit the front wheel and then pump the suspension to get the forks straight - check that the top and bottom yoke are exactly parallel before tightening all the bolts in the yokes, and that's it. Note that the forks do have (expensive) air caps, but we can't find any info on what pressures to use etc, so we'll see how it goes...
	These are the original forks and hopefully this shows what a good job dynasurf did... when we got the forks back they were straight and all the pitting had been filled. Dynasurf charged us £80 and took about two weeks to do the job, give them a ring on 01270 793032.

boing...shocks

Hmmmm, the rear shocks with the bike are knackered and so we fitted these ones of the same length that came of a husky we have, sadly they are rubbish and compress way to easily so we can either get the originals rebuilt (costly) or find some alternatives...anyone with a pair of ohlins piggy back shocks with 40cm between centres please get in touch!

The costs so far...

rechroming the fork legs £80 plus new seals at £11.81 each and a litre of fork oil for about £5...rebuilidng the wheels will cost about £80 for a rim £30-40 for spokes and £30 to build - yikes!

and here's the plan...

1	Get the Bike...
2	Strip It
3	Clean it
4	Paint it
5	Engine
6	Suspension/wheels
7	Test it
8	Race it
9	Costs and Parts

crack...wheels

	The tires were cracked and ruined so we decided to fit some news one, sadly when we got the tires off we noticed that the rim was cracked, this meant new rims at the least - given the state of the spokes we decided that the best option was to completely rebuild the wheels. The front rim was virtually square and so the expenses began to mount...
	Initially we decided to just replace the rims, so on the back wheel we tried to undo the spokes...sadly this got a bit frustrating after three hours, so we just extracted one of each of the four spoke types from each wheel and then hacksawed the rest...Before doing this you should measure the offset of the rim. No, we didn't realise that the rim wasn't always in the middle, but we do now becuase the guy who rebuilt the wheels told us that we were stupid for just taking in the hub...We stripped and painted the hubs before taking them off to be rebuilt
	After a week and a few hundred quid we had sparkly akront rims and shiny spokes. Now we could have done the rebuild ourselves and saved about £30 - but realistically our limited skills are taxed by rebuilding a fork, getting 36 spokes to the right tension really isn't worth the three days it would take us. Having spent so much on the wheels (about a quarter of the entire budget) we had to economise on tires and went for some"super-high-quality" cheng-shings, for running in the bike these should be fine. Sadly they were so stiff that they took superhuman strength to fit - leading to much scratching of the new rims...
	Having had the wheels rebuilt and fitted the tires it just remained to fit the chain and sprocket. Note that the sprocket bolts need to be proper counter sunk ones and not just any old bolts...
	When the chain is fitted you first need to cut it to length using a chain splitting tool and then fit the split link, note that the open end of the link should face away from the direction in which the chain is moving, if you fitted it the other way it could catch on something like the tensioner and ping off - not nice...
	The CR roles again (although not under its own steam) £500 quid badly spent - check that the forks, shocks and wheels are serviceable before parting with your hard earned for a project... We got our wheels rebuilt at Bill North Motorcycles (01905 27988), who are a local firm who did a good job and specialise in wheelbuilding.

What we learnt this time...

Refurbishing a set of forks isn't too difficult although a certain amount of trial and error will be involved in setting them up for yourself. If you've got the budget it may be worth taking them to a professional company. Wheels are expensive and a project with shagged rims and suspension is going to cost (compare the honda to our suzuki and you are looking at half the cost...)

the next installment is testing the bike>