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Marketplace => Wanted => Topic started by: Kenneth S (222) on February 24, 2014, 06:39:14 am

Title: 5.5 - 6.5 Rear Spring for 84 Honda CR250
Post by: Kenneth S (222) on February 24, 2014, 06:39:14 am
Dimensions,

Exact Stock Length is 275mm but anything from 260 - 275mm will work.

ID 56mm

OD 78mm

Contact Kenneth 0411 639 649
Title: Re: 5.5 - 6.5 Rear Spring for 84 Honda CR250
Post by: Kenneth S (222) on February 24, 2014, 06:04:56 pm
Ken , can you be a bit more specific . In 240, 250 and 260 mm length  ID 59-60 I have many options .

Hi Lozza, I've updated the specs above.
Title: Re: 5.5 - 6.5 Rear Spring for 84 Honda CR250
Post by: JohnnyO on February 24, 2014, 07:16:07 pm
I think Walter is asking what spring rate you want, I don't think there's such a rate as 5.5-6.5 and there are about 10 available between 5.5 and 6.5 
Title: Re: 5.5 - 6.5 Rear Spring for 84 Honda CR250
Post by: Ted on February 24, 2014, 07:30:17 pm
Teknik have 28 springs in stock to suit in 5.6

He needs to know if it is 56mm ID both ends.

If you can supply both end ID he will supply collars and spring for $150 and I will bring to Cessnock on Friday.
Title: Re: 5.5 - 6.5 Rear Spring for 84 Honda CR250
Post by: Kenneth S (222) on February 24, 2014, 08:10:53 pm
Thanks Guys, Ideally I'm looking for a cheap 2nd hand one sitting on someones shelf to try out. I am not sure what rate suits me.

At the moment the bike has a 4.1 in it which is too soft. When I go on the Racetech website and use their spring rate calculator for this model it tells me at 88Kg, I need a 7.2. That seems very high to me so I am willing to try something between 5.5 - 6.5 as a starting point to see how it feels. It may well work out that the bike will still feel too soft and I do need 7.2 but a spring at a rate between 5.5 - 6.5 will at least be a vast improvement over what I have now.
Title: Re: 5.5 - 6.5 Rear Spring for 84 Honda CR250
Post by: Paul552 on February 24, 2014, 08:16:17 pm
Ken

Off the top of my head I don't know what is in mine but I'm happy for you to try mine out if it helps you?
I won't be at  cessnock but will be at the vinduro ?
Title: Re: 5.5 - 6.5 Rear Spring for 84 Honda CR250
Post by: Kenneth S (222) on February 24, 2014, 08:27:53 pm
Ken

Off the top of my head I don't know what is in mine but I'm happy for you to try mine out if it helps you?
I won't be at  cessnock but will be at the vinduro ?

Cheers Paul. Very kind of you, I'll see how I go, I hope to have it sorted this week
Title: Re: 5.5 - 6.5 Rear Spring for 84 Honda CR250
Post by: Ted on February 24, 2014, 08:33:15 pm
Ask yourself this Ken " why does he have 28 springs in 5.6"

Standard is 4.5
Title: Re: 5.5 - 6.5 Rear Spring for 84 Honda CR250
Post by: Kenneth S (222) on February 24, 2014, 08:48:56 pm
Ask yourself this Ken " why does he have 28 springs in 5.6"

Standard is 4.5

Different bikes have different leverage ratios Ted. Anyway, I just need to feel what something in the 5.5 to 6.5 range is like to make my own assessment. There seems to be so much conflicting information out there.
Title: Re: 5.5 - 6.5 Rear Spring for 84 Honda CR250
Post by: JohnnyO on February 24, 2014, 09:26:12 pm
I've fitted 5.6 shock springs to several 84 CR500 's, that rate seems to be on the money for most.
Title: Re: 5.5 - 6.5 Rear Spring for 84 Honda CR250
Post by: Kenneth S (222) on February 24, 2014, 09:55:46 pm
I've fitted 5.6 shock springs to several 84 CR500 's, that rate seems to be on the money for most.

Great thanks. That helps
Title: Re: 5.5 - 6.5 Rear Spring for 84 Honda CR250
Post by: Paul552 on February 27, 2014, 09:12:33 pm
I've fitted 5.6 shock springs to several 84 CR500 's, that rate seems to be on the money for most.

Great thanks. That helps

Hey ken I am interested how you went with this?
Was the bike better?
Title: Re: 5.5 - 6.5 Rear Spring for 84 Honda CR250
Post by: Kenneth S (222) on February 28, 2014, 04:39:23 am
I've fitted 5.6 shock springs to several 84 CR500 's, that rate seems to be on the money for most.

Great thanks. That helps

Hey ken I am interested how you went with this?
Was the bike better?

I'll find out tomorrow Paul. It feels better in the workshop. I'll let you know.
Title: Re: 5.5 - 6.5 Rear Spring for 84 Honda CR250
Post by: Nathan S on February 28, 2014, 09:04:43 am
Anything in the 5.x range will be too soft. I doubt that 6.5 will be enough.

I've got the RaceTech recommended 7.2 or 7.4 in mine, and it feels spot on (based on the sags and the little riding I've done on the bloody thing).

Don't be worried by the big jump in rate - they ran silly rates in them back in the day. The stock forks springs a .29 or something similarly insane - when you'd be wanting something up around 0.45s.
The shock linkage ratio is whacky by modern standards too. 
Title: Re: 5.5 - 6.5 Rear Spring for 84 Honda CR250
Post by: FourstrokeForever on February 28, 2014, 10:14:09 am
I had .48 forks springs and 7.2 rear spring on my '86 CR250 and it worked great. At the end of the day, it all comes down to your weight and riding style so spring rates is as personal as handle bar position.
Title: Re: 5.5 - 6.5 Rear Spring for 84 Honda CR250
Post by: JohnnyO on February 28, 2014, 12:45:59 pm
Anything in the 5.x range will be too soft. I doubt that 6.5 will be enough.

I've got the RaceTech recommended 7.2 or 7.4 in mine, and it feels spot on (based on the sags and the little riding I've done on the bloody thing).


Don't be worried by the big jump in rate - they ran silly rates in them back in the day. The stock forks springs a .29 or something similarly insane - when you'd be wanting something up around 0.45s.
The shock linkage ratio is whacky by modern standards too.
The std shock spring rate on the 84 CR500 is 4.5kg. The 81/82/83 CRs ran heavy spring rates in the 7kg range and strange linkage ratios, 84 was back to a more modern type ratio and spring rate.
Title: Re: 5.5 - 6.5 Rear Spring for 84 Honda CR250
Post by: Nathan S on February 28, 2014, 04:16:22 pm
Yep, but the standard spring rates were still best suited to 45kg riders - meaning that the correct spring rate is up around 7.0 for most riders.

XRs seem to be the only other common bikes that need 7kg/mm springs for <100kg riders.
Title: Re: 5.5 - 6.5 Rear Spring for 84 Honda CR250
Post by: Kenneth S (222) on March 05, 2014, 06:24:56 am
I put a 6.5 in and it was a completely different bike. I was able to hit long whoop sections with more confidence than ever before. The damping adjusters worked better. What a difference!
Title: Re: 5.5 - 6.5 Rear Spring for 84 Honda CR250
Post by: Paul552 on March 05, 2014, 09:45:22 am
Hey Ken
Did you change the front as well? Or just the rear?