Fork Swap vs. Valving/DMr Cartridges
 

Hey all,

New chicken owner here, with a lovely (if not slightly dented) craigslist stocker. I've been slowly getting the bike back into a happy place (Mosfet comes in next week, Manual CCT goes in tomorrow, carb sync, fluids etc.) and I'm just about ready to address the suspension.

My intention for this bike is to have a "do everything" from commuting, to canyon riding, potentially a trackday, and a lot of adventuring.

So I'm wondering what experiences people have had either just upgrading the stock forks or doing full front end swaps. Why did you go the way you did? Does anybody have experience with both?

Thanks in advance! Tomorrow is my "reroute carb breather" day, so hopefully I won't get the sputter after hard braking.

I revalved the stock forks. I see little point in fitting stiff forks to a frame that is not set up for it. Im running gold valves and custom rebound stack.

I ride track with it and next time out ive been told I have to be in the second from the top group. Top group being the top racers.

That is a tough one. As spokes said you can get very good track results with mods. For me the clincher is that if you get a good deal on an USD fork and sell your stock stuff it can actually be cheaper(!).

Plus it is even easier to do a front end swap than gold valves & springs.

There is more to it than that but just to give perspective. For me one of my hawks has a cbr1000 front and the other is getting a 600rr as soon as its warm out.

That is exactly my struggle!

I'll have to do some research, but I do have some 02' R1 fork legs available to me. It might be as easy as some new bearings, and a wheel/brakes but I don't know for sure.

Anyway, that's why I was asking for any stories/ personal logic to justify the direction they went. Interesting perspective that the frame isn't set up for a stiff front end. Anybody feel like expanding on that?

The logic there is that the frame is not the stiffest one ever made and the stiff forks would be overkill. I don't tend to agree as the other mod is a braced swingarm and yet another a fork brace.

I have seen many older frame designs do very well on the track with modern usd forks. I think the more you stiffen the better (within reason).

Some guys worry that the stiffer forks may transfer the load elsewhere with bad results but I have seen a lot of bike to disprove that.

It also depends on if you are a top racer using it for only racing. 99% of street guys will never push the bike to those limits and that last 1% is probably lying to themselves.

Its a preference thing but like I said it may be actually easier to just put on superior forks so to me why not?

Do you not have to change the springs and valving when you do a front end swap?

In theory, yes. But in my experience the cbr1000rr fork stock is worlds better than a vtr fork stock. (which isn't saying much).

The bike would benefit greatly from modding the forks though.

I have a '07 CBR1000RR front end that I'll be installing as soon as I get this dang front wheel repaired. Anyways, a suspension tuner told me that the CBR front end is sprung for a 190-200lb. person and the valving is perfectly fine for street riding with a track day or two in the mix.

As far as other front ends go, it all depends on which one you choose. As far as I have found, a lot of the jap front ends are sprung pretty light.

Mine with a brace and r/t valves is great. No need to change.

Well from my experience with front end swaps you guys are missing one important thing.

While the stock forks can be made to work pretty damn well the biggest "improvement" with a later front end is the brakes.

Going to 320mm rotors and better calipers is where things really take a step up.

So while the forks themselves are a small improvement the forgotten benefits are where you really get paid dividends on a fork swap

Ah, YES 8541, mongo brakes. Forgot to mention how changing to a full radial setup meant to slow a racebike all day long is awesome.

Huge safety factor improvement.

Strange. My stock brakes with braided lines and DP HH+ pads handle a 20 min track session with no problems. And with more power than the chassis can handle.

Im all for fork swaps where needed but this one doesnt seem needed. I have done a KX swap on my KDX200 as the bitch kept throwing me over the bars.

Spokes, stock brakes on this bike are not strong. Being able to ride around it is just that, riding around it.

There is a reason Honda and every other oem put stout radial brakes on their racebikes. The stopping power is way more as is the fade resistance.

If you are on the track the LEAST you should do is put on the CBRF4i brakes on. They are a world better than stock and you will be on here posting what a revelation they are.

Its a cheap swap too. PLUS you can get vesrah rjl pads for the cbr brakes which are a quantum leap in power and feel.


I had a friend ask me why upgrade brakes if the stockers can lock the wheel... Well, its because with more headroom you have a greater power margin, meaning a less steep curve leading up to lockup. You are not using 96% of your overall power. You are using like 60% so modulation is easier takes less concentration during corner entry. Seek out a pro rider or instructor (who is a real racer) at the track and they will agree with this logic.

Ive been told next time out Im running in the second to top group at our track days as my lap times will be mid pack for them. Above that is the full racers on Superbikes. Only time on a lap Im 2 finger braking is when we have to come down from 220kph to 90kph on one turn. Apart from that Im 1 finger braking.

The bike in current form is faster than I am. But once I get a few more seconds off my lap times I will be at the limit of this chassis with out major changes. But Im at the limit of what my body can handle. So here I will probably stay and enjoy the VTR for what it is.

Spokes, what track are you riding? Do they race there? What was the lap times of the winning expert 600s?

As a reference, on a track day I go out in the fastest group that ride 1000cc 150+hp bikes. I lapped all but one bike (meaning passed every 1000cc bike twice per session).

I was riding a stock 50hp ninja ex500.

So maybe track days are not the benchmark for speed.

Hampton Downs. Im doing 1.28s. Top guys are 1.10s. Huge speed difference.

Ive ridden a 180hp Gixxer 1k round there. I didnt get lap times but it was a ton faster in a straight line. Hawk lacks the raw speed in a straight line for fast times.

It has been suggested many times I get a 600 and go racing but my physical limitations are to much of a risk in my view.

I to have passed R1s, Gix 1ks etc. But one being properly ridden will pass a Hawk with ease.

Right so there is proof you can use stronger brakes. At the faster speeds, or to even get there racers are taught to be either full throttle or full brakes. No commuting/neutral throttle.

I am just saying stronger brakes are very useful anywhere. Especially the track.

Lol, I dont need more brakes. Bike has not got the speed to use it.

Only thing it really needs is a swingarm brace. If your a bit rough on the gas out of a turn it can be a bit exciting.

Don't forget guys: when doing a complete front end swap the new forks also need springs and a full revalve! Just because you have a set of USD forks doesn't mean they are any better than your stock parts. In fact, with most cases the parts inside are the identical same as the stock VTR forks. The springs and valving is what generates your performance, not what they look like on the outside.

Thank you for bringing this point up. In hindsight it should have been obvious. Not untill I had collected all the parts for the swap I realized that the forks would need to be sprung and valved as well. The price of which is what's keeping me from finishing the swap.
Not saying that it can't be done, but I don't see how a swap could be any thing but much more expensive than a full rework of the stock forks, including a brace, even selling the stock components. Which by it's self seems a long shot.

I don't race. But from what I have read about autos, stronger brakes make all the difference in your time.
If you have the tires, brakes and courage, the driver can go so FAST (passenger is praying for past sins because he knows it is impossible to make this curve) into a corner and then claw down to a speed that suddenly makes it possible.
So USDs look cool and have better brakes. Oh, and what about fun factor?
Some can't resist the call to tinker and may find modifying their bikes gratifying. It may not be cost effective, but neither is playing golf.

This is very true and I agree. When i did my KDX fork swap it was mainly because the stock fork underhang would get caught in ruts and send me over the bars. The USDs fix that but i had to re-valve them to suit my weight and trail riding.

I never had the CBR fork on my SH, but I doubt that without proper valving and springs it would be a significant improvement over the stock VTR fork.

I know for sure that on my bike a superbrace and JDM valves/springs improved the front end stiffness/stability dramatically and definitely enough to make the rear suspension the mechanical component limiting the ride. Inside high speed sweepers the front of the bike felt rock solid but the rear was wobbling all over the place. So I replaced the rear Showa with a Fox TC properly sprung and that made the bike run as planted as it never had before on both the rear and the front.

With these suspension mods I feel I can ride safely very close to maxing out the potential of my stock engine and I don't miss the USD fork. I would rather brace the swingarm since like NZSpoke wrote, it "gives in" a bit when you come out hard from a turn.

Bottom line in my opinion if you want to get the best riding improvements out of the money invested in suspension mods, skip the CBR conversion and go with the JDM front. Then invest the spare money in a better rear shock. If money is not a factor, get the USD forks+spring/valves+Ohlins rear shock+CF wheels+.......:)

I am not sure how many of you remember what stock vtr forks are like.

Installing CBR forks is a HUGE improvement over stock vtr forks. Night and day. Way more adjustability, no harsh bottoming, way more planted.

I agree reworking them will improve them but just the swap to a superbike front end designed by Honda to be on its fastest racebike is a major step up.

Well I guess I'll add a bit here as it seems there is still confusion about this swap.

First it is hard to have a discussion about this with folks who have never ridden a bike with the swap but believe it isn't worth the time.

Goes back to the old adage.... the best you know is the best you have ridden.

As someone who actually has run both a well set up stock front end and the current USD that I have on there now and I can tell you there is a world of difference.

Lets look at the components as there is more than just forks involved.

The forks themselves...USD forks are stronger, lighter and stiffer than the conventional VTR set up.

The whole valving and spring set up is a non issue to me as you have to do that to any front end you run.

Now lets look at the bits that seem to get forgotten or overlooked.

First the brakes, going to 320mm rotors is a Big improvement and if you wanted to upgrade the stock set up the cost of rotors and the caliper adapters would cost more than sourcing a complete USD front end.

Next is the big one...... the triple clamp.
The stock VTR triple is about as stiff as al dente pasta.
Back in the club racing days the stock class F3 guys fought this issue every time they went out.

So while some might say there is no real difference, I am not in that camp.
The front end swap completely transforms the bike from being vague and a bit sketchy into a well planted and running on rails.

You guys can go over this till the cows come home but from someone who has actually run both all I can say is I would never own a VTR with a stock front end.

Carry on. ;)

It is obvious there will be a big improvement in stiffness of the front end. Valving aside. But this is put in a frame that is known to be soft and is also known to highside with sticky rubber on. The frame and swingarm absorb that load in a turn until you get on the gas coming out of it and that flex gets released. Adding a uber stiff fork will make this worse. Yes a swingarm brace helps.

Ive ridden Gixxers, CBR1ks etc on track and they are in a different league to the VTR in terms of handling. The core problem on the VTR is the frame.

I dont love the VTR for its power but its personality. Its alive. No other bike has given me that feeling. But lets not kid ourselfs into thinking its a giant killer. Its just a very fun bike to own and ride. I have 5 bikes and its the one I get excited about riding.

8541 well said. I agree completely.

I have ridden stiffer as well as flexier bikes. Even bikes less stiff benefit from stiff forks. I know this from the grids full of last gen bikes on the ultralight supersport grids that have stiff forks and have taken huge time off their laps.

That whole tuned flex/too much flex thing is mostly conceptual compared to actual results and thousands of track hours by expert racers. (IMHO).

You have to really wind up a bike to get it to do weird stuff based on flex. Very few riders do that (like 1/10th of a percent). I really doubt anyone on here does it. I sure don't.

So unless Nicky Hayden is hiding on here, stiffer forks are an improvement.

Well not sure where you have gotten your data but from riding my bike with the forks and swingarm brace for years now I can say my bike has never exhibited the issues you have listed...... Though I think it is because you might be thinking track bike while the rest of us are talking street bike.

Yes I can get the frame to start to wind up but on my bike you need to be running at over a ton to get it to happen.

As this is faster than my "normal" pace, on the street, I have found no need to brace the frame. If needed bracing the frame is not a big deal and is easy to do.

Yep the VTR is no track weapon and was never meant to be. Again I agree, at track speeds the frame is an issue but easy to address.
Though I am talking the benefits gained on a street bike personally.... though I did forget to add a lighter front wheel to the benefits of a USD fork ;)

I agree it is a great street bike..... but I can also tell you that it is a completely different bike with good suspension and a braced swingarm.

I know my bike was working well with the stock bits all set up by Lindemann Eng. with a fork brace (which does really help).

Then I did the swap and I can tell you that the bike now would run circles around the bike then.....no question in my mind.

So run whichever set up you like...no worries but I will stick by my statement that after running both, I would never have a VTR with a stock front end.

I cannot imagine how flexible forks will help with handling. Forks are doing lot of work in one axis, another forces will not improve anything.

This thread has increased my interest in a fork swap. I have read Tweety's thread on the subject many times. It seems like the 954 may be the best option.
There is a nice 05 CBR1000RR fork set available to me but I am reluctant to "trim" the fairings. Are there any photos available that shows the extent of the trimming?
Also, what would be a good strategy for finding parts? Focus on specific bike donor parts or find the best condition/price available and adapt those?
I guess the question is, for those who have done this, which parts would you look for if you had to do it all over again with a time frame of about 2 months to find parts?
Something like this?
http://www.ebay.com/itm/00-01-02-03-...ht_1068wt_1362