Front Fork Spring Advice ...?

[Guest chat_vmax]

The below is a cut and paste from Racetechs site,,

I am a very spirited rider,, i weigh 170lbs,, often burying the spedo,, and having to bkrake fairly hard,, the only and bigest complaint i have about my 1994 vfr 750F is that the front likes to dive easily,,

so i pluged in the value for racing...

is that to agressive,,, ??

am i on th eright chart..?

amount and weight of oil PER shock would be much appreciated...

Thanks Much

94-95 Honda VFR750

Select Type of Riding:

Racing

Enter Rider Weight (without gear): lbs OR kg.

Rider Weight: 170 lbs.

Recommended Spring Rate: 0.920 kg/mm (use closest available)

Stock Fork Spring Rate (measured): .701 kg/mm (stock)

Available FRSP S3534 Series Springs are:

Part Number Description Price Select to Buy

FRSP S3534080 RT FRK SPR 34.7x340mm .80kg $109.99

FRSP S3534085 RT FRK SPR 34.7x340mm .85kg $109.99

FRSP S3534090 RT FRK SPR 34.7x340mm .90kg $109.99

FRSP S3534095 RT FRK SPR 34.7x340mm .95kg $109.99

FRSP S3534100 RT FRK SPR 34.7x340mm 1.0kg $109.99

[fallzboater]

I would go more towards the soft side of Race Tech's recommendations, especially if you're not going to also replace the rear spring (or whole shock, ideally). Tracks are better graded/smoother than what a lot of us ride in the mountains. If you're not going to change your rear spring, or your roads aren't that great, I'd suggest you consider 0.85. In any case, I don't think you'd want to go stiffer than 0.90.

[Guest]

If you are really interested in buying Racetech springs, call them. They are very knowledgeable and can tell you everything you need to know. If you arent actually racing on a track I would opt for the .90 spring since it is closest without going over what they recommend. I would also ask them about revalving with their gold valves. I did the spring and valves on my 06 and have been very satisfied with it, even though I dont ride as hard as you do. If you tell them what YOU want out of your suspension They will give you ALL the info you need to set it up for YOUR individual needs. Try it, youll like it.

^ Also like he said, you should respring the rear, or better yet, replace with an adjustable unit. Then make sure to set the sag at both ends. This turned my 06 into a totally different ride (for the better). Good luck with whatever you decide.

[Guest]

If your worried about it being aggressive, why did you put in "Racing" when I would gather you are a street rider. Sorry, but going fast in a straight line doesn't make you an aggressive or good rider. Use the OEM recommenced oil level and viscosity if you are not upgrading your valving. The VFR has cartridge style forks that have valving which is designed for a fixed viscosity of oil. Raceteck springs are good springs, find a good aftermarket rear shock on ebay, and then do a rider school or track day if you want to ride aggressive. There are quite a few how-to posts on this web site, I would suggest read the ones about suspension.

This link is about setting sag.

http://www.vfrdiscussion.com/forum/index.p...;showarticle=30

Good luck

[Earthshake]

I would go more towards the soft side of Race Tech's recommendations, especially if you're not going to also replace the rear spring (or whole shock, ideally).

I weigh 180 and went with the Racetech 0.90 springs, gold valves (compression only) and the recommended 5W oil. I am very pleased with the forks but the rear needs help. I have done the the 929 shock conversion but I can't set proper rear sag until I respring. You need to heed fallzboaters advice on doing the rear as well, and favor the lighter side of their spring recs.

[Guest]

I would go more towards the soft side of Race Tech's recommendations, especially if you're not going to also replace the rear spring (or whole shock, ideally).

I weigh 180 and went with the Racetech 0.90 springs, gold valves (compression only) and the recommended 5W oil. I am very pleased with the forks but the rear needs help. I have done the the 929 shock conversion but I can't set proper rear sag until I respring. You need to heed fallzboaters advice on doing the rear as well, and favor the lighter side of their spring recs.

if i dont want to revalve,, just go with the .90 spring and a little heaver oil is there a way i can flush the forks out well without disassembly,,

i plan on taking them off the bike,,, can oi wash / flush them out with some solvent [ please recoment one ] and leave them hanging up side down for a week or so...????

Thanks again for any advice...???

[Guest]

Heavier oil won't help anything

[Guest]

Yes you can flush them with solvent. Just make sure you drain out all the excess.

[Guest]

Yes you can flush them with solvent. Just make sure you drain out all the excess.

can u recomend an exact solvent, im a bit scared to use anything unless u guys have something in mind ??????

thanks again

[Guest]

You can use mineral spirts or something like that. Just pour some fork oil in the forks and flush out any residual solvent. Make sure you pump the damper shaft and the fork tube when you are cleaning them.

Let me elaborate a bit on the oil viscosity, you want the forks to be able to move freely but not bottom, if you put in oil that is thicker then the valving is designed for it will slow the forks down to much. The valving in cartridge forks is made of shims that deflect when oil is forced past them. Thicker oil is useful in the older style of damper rod forks. Just try changing the springs you will be surprised at the change. In my experience heavier oil will slow down your forks to much and can cause the front tire to skip under hard braking if you go over an uneven surface.

[Guest]

You can use mineral spirts or something like that. Just pour some fork oil in the forks and flush out any residual solvent. Make sure you pump the damper shaft and the fork tube when you are cleaning them.

Let me elaborate a bit on the oil viscosity, you want the forks to be able to move freely but not bottom, if you put in oil that is thicker then the valving is designed for it will slow the forks down to much. The valving in cartridge forks is made of shims that deflect when oil is forced past them. Thicker oil is useful in the older style of damper rod forks. Just try changing the springs you will be surprised at the change. In my experience heavier oil will slow down your forks to much and can cause the front tire to skip under hard braking if you go over an uneven surface.

thanks very much for that extra knowledge,,, much appreciated,,

so the stock weight is 10wt i believe ??

and the amount of ait at the top of the shock with NO springs inserted is??

[ please verify that is the correct method,,, no springs and fork fully extended,,] then poor fluid into unit until air gap at top = ?

then insert springs and the fork cap...?

Thanks Much...

[Guest]

On the 4th gen you're supposed to use Honda SS-7 which I think is 5W, The correct level is 177mm from top of the tube to oil when spring is removed and fork is compressed. Make sure you stroke the fork and piston rod several times to get the oil in the cartridge (pump the piston rod slowly, you'll see why :D )

[Baileyrock]

I am a very spirited rider,, i weigh 170lbs,, often burying the spedo,, and having to bkrake fairly hard,, the only and bigest complaint i have about my 1994 vfr 750F is that the front likes to dive easily,,

so i pluged in the value for racing...

is that to agressive,,, ??

I don't know where you live, but riding where you "often burying the spedo,, and having to bkrake fairly hard" is Not ideal for street riding for many reasons let alone the non stop dancing with the devil. Best saved for the track, the PACE is the safest and most enjoyable to ride on the street for your safety and the future of our sport!

Now off the box and to your question, as mentioned Race Tech numbers are on the very firm side so a step or two lower will provide you a more usable compromise. Raising the the oil level 10mm with help some along with the proper springs.

Also check under our "bargain finder" section for Sonic springs, less money and most likely better springs. :goofy:

http://www.vfrdiscussion.com/forum/index.php?showtopic=30860

[Earthshake]

Yes you can flush them with solvent. Just make sure you drain out all the excess.

can u recomend an exact solvent, im a bit scared to use anything unless u guys have something in mind ??????

thanks again

kerosene

[Guest]

Yes you can flush them with solvent. Just make sure you drain out all the excess.

can u recomend an exact solvent, im a bit scared to use anything unless u guys have something in mind ??????

thanks again

kerosene

[turtlecreek]

Yes you can flush them with solvent. Just make sure you drain out all the excess.

can u recomend an exact solvent, im a bit scared to use anything unless u guys have something in mind ??????

thanks again

kerosene

:blink:

[sailcycle]

I just bought an Ohlins 46HRCL and I know that I'll need to do some serious work to the front end to balance things out. I've read Slammer's featured mod on the Race-Tech setup he performed and I'll probably head in that same direction.

A lot of posts I've read on the subject of spring rate have people installing .90 or .95 springs. Race-Tech's site suggests that my 180lbs would be best suited to a .991, which seems weird given that their highest rate is 1.00. As a matter of fact, to qualify for their lowest rate spring, a .85, a street rider would have to weigh 85 pounds without gear. Hell. My Thanksgiving dinner weighed more than that. To "qualify" in the .90 range, a rider would have to weigh 120lbs. Fess up. How many 120lb VFR pilots do we have out there? :huh:

I know that everyone says that Race-Tech tend to go heavy with the spring rate, but this just seems silly. Thoughts???

[Baileyrock]

A lot of posts I've read on the subject of spring rate have people installing .90 or .95 springs. Race-Tech's site suggests that my 180lbs would be best suited to a .991, which seems weird given that their highest rate is 1.00.

I know that everyone says that Race-Tech tend to go heavy with the spring rate, but this just seems silly. Thoughts???

Race tech sux, at your weight I would go with the .90 if you do combined riding or the .95 if all you do is hard charge twisties and between a 18-19 kg rear spring. If you just commute and tour solo a .85- 18 sounds good.

at 195 lbs I'm running a .95 front with revalved forks and a 19kg spring on an Ohlins rear and only rail twisties and it feels good to me. :huh:

[VFR4Lee]

Interesting. Someday soon I'll gave to get off my ass and update / replace my suspension.

It's only original with 64k miles. :rolleyes:

Hmm, what to do? I'm printing this thread. :pissed:

[Guest]

My $0.02 I weigh about 150 I put the 1.0 racing springs in, I am a very aggressive rider. I seem to be blind to suspension set up because all I've ever had is crap. I just compensate. I like what I did to the front end though. It used to dive every time I hit the front brakes but it no longer does. BR told me that I would have probably been happier with a .95 spring though. As you know he is our resident suspension expert, just ask Hurricane249.

[jeremy556]

It used to dive every time I hit the front brakes but it no longer does.

But isn’t that what the suspension is supposed to do? The greatest load on the front end is hard braking; you should expect near or full compression under hard braking. Otherwise, what is that suspension travel for? You are not going to be creating a larger load via a bump in the road than you will be by braking.

For a long time I had .95 springs and too heavy weight oil, I think 10 weight. My forks never bottomed, or ever even used up the majority of the travel (I had a zip tie on one fork tube).

When I revalaved my forks with gold valves and used the 2.5 weight oil, my forks were much softer and more complaint, and I started using all of the suspension travel again. The bike handles MUCH better in all conditions, is much smoother, and easy to ride in all conditions.

Don’t confuse different with better; just because it is different, doesn’t mean it is correct.

[CornerCarver]

It used to dive every time I hit the front brakes but it no longer does.

But isn’t that what the suspension is supposed to do? The greatest load on the front end is hard braking; you should expect near or full compression under hard braking. Otherwise, what is that suspension travel for? You are not going to be creating a larger load via a bump in the road than you will be by braking.

For a long time I had .95 springs and too heavy weight oil, I think 10 weight. My forks never bottomed, or ever even used up the majority of the travel (I had a zip tie on one fork tube).

When I revalaved my forks with gold valves and used the 2.5 weight oil, my forks were much softer and more complaint, and I started using all of the suspension travel again. The bike handles MUCH better in all conditions, is much smoother, and easy to ride in all conditions.

Don’t confuse different with better; just because it is different, doesn’t mean it is correct.

:rolleyes:

Jeremy nailed this one. Why have a 120mm of travel if you are only using 80mm of it (and 35 of that is the sag)! Your suspension can be much more compliant and keep the front tire in contact with the road.

1.0 springs and heavier oil with stock valving and a 170 lb rider with gear would only be at home on a fast smooth track or road where you were concerned about constantly G-ing out the suspension.

[Guest]

dont want to seem like Im one of thoes guys that JUST get the info they want and blow off all the advice..

first and foremost I want to say amen to the guy who told me that burying my spedo often is not = to a good rider ,,,:-) so true..

Point well taken,,,,,

with a built 99 blackbird and a 06 busa also in my stall i agre 100 percent with that..

BUT I would also add that good [ skilled ] but stupid riders like me at 47yrs old do often burry there spedos,,,

I have been sitting back ane just reading and learning very much about my vfr and suspensions in general,,,

thanks for all the extra info and things to think about,,,!!!!

PS: i fly a desk about 50 hrs a week,,, gettin my hands filthy dirty, cussin up a storm at the local bike stop, smokin and arguing / riding with the local 1000cc + riding 20 something year olds and taking it down our 3 1/2 mile straight away we have here at the base of the most beautiful mountains in the world in western pa reminds me im not dead yet,,,

and if i plow a deer or turn into powered hamburger,,, well its so much better than gettin hooked to a kemo machine with less than 2% chance of survival,,,, may be bad logic but ill guarentee that you will never read one of my great published sientific findings after im gone :-)

[enzed_viffer]

I weigh about 200 pooondz, and have 0.95 Sonic Springs in my '01 VFR, and 12W oil (started with 10w, but there was insufficent damping).

While they're a lot better than the 0.74kg/mm stock springs, 0.95 is a little too bouncy. I plugged the info in several times into Sonic's calculator, even tried changing the parameters to see if it was right, and contacted them to check, but it still came up with 0.95.

With some Gold Valves or similar, I'm sure the damping in my bike's forks can be improved, but I wish I'd gone with lighter springs.

In your case, given that you're much lighter than me, I wouldn't go over 0.85. That's still 15% stiffer than stock, whereas 0.95 is around 28% stiffer - a very big change.

[Baileyrock]

0.95 is a little too bouncy.

When you say bouncy, what do you mean?

All the springs do is hold the bike up, the dampening controls everything(spring, transitions, etc.)

I would think with stock valving you would want lighter oil ? The heavier fork springs should require less compression dampening and more rebound and w/o revalving it will always be a compromise.

Also did you increase the rear spring rate at the same time??? If not the bikes balance will be off and the stiffer fork springs will be transferring more weight to the rear causing the front to tend to just bounce across road imperfections instead of absorbing them. I had this same issue on my 02 when I had the forks revalved/resprung (.95) rebuilt, but left the stock spring rate on my rear Ohlins. In general riding the forks felt worse as the bounced across the road feeling way to stiff, but braking and some hard riding improved some. The bike was completely transformed once I installed the correct rear spring to match the stiffer front and BOTH ends worked and felt better. This softened the feel of the front too as the stiffer rear spring transferred more weight to the front making it work more/better. :thumbsup:

Transformed thread

http://www.vfrdiscussion.com/forum/index.php?showtopic=19943