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Hello all, brand spanking new Guzzi rider here. I know very little about these bikes, and this is most modern machine I've ever owned. I posted this on the Guzzi Tech forum as well...
 
I purchased a used 2001 v11 sport, loving it very much, already pondering some upgrades. I was wondering if it would be relatively easy, or even possible, to swap the front end off my bike and replace it with that of a 2008 (or later) Griso 8v. Mainly for the benefit of having radial mounted calipers.
 
Has anyone ever done this? I'm not familiar with all the specs, but is there any reason to think that it wouldn't work? Or that it wouldn't be a good idea?

The accompanying question is, where would I get a good used front end? There are lots of options on ebay for other bikes. (I'm currently watching some auctions for GSXR front ends for another project.) But used Guzzi parts are virtually non existent there, understandably so given how much smaller the "user base" is. This also begs the question: does anyone have any experience installing the front end of a modern Japanese bike onto the v11sport? Which models offer the easiest swap?

Any suggestions or insights would be greatly appreciated.

Thanks!

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I think one of our members installed a GSX-R front fork assy. on their bike.. It didn't use the radial mount calipers. 

Are you sure this is going to be cost effective ?

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I'd like to figure out what is possible first, before worrying about the cost...

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any Griso being parted out will probably be wadded up in the fork area.. best look to Suzuki.. why do you need radial mounted brakes?

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I have swapped to GSXR front end on one of my Guzzi's, a Daytona (much related frame wise to a V11). A GSXR front end would be a better choice. They are more common, so easier to get and cheap. They are also better forks, that  use radial brakes (at least most late model versions do), a lighter front wheel, and parts/upgrades for them are easy to come by. Most suspension guys can make a GSXR fork do whatever you need it to do.

Also, the swap was not that hard, consisting of a complete GSXR front end (forks, wheel & discs, and brake calipers, I used a Brembo radial M/C), using tapered steering bearings from a Suzuki DRZ 400, and making a few assorted brackets and what not for things like the headlight and turn signals. I used a front end from a '04 GSXR 1000. I had a suspension guy spring and valve it for me. Further research and measuring says that an '06 -'07 GSXR 750 front end is actually a better choice. But either will work and I am sure some others will as well. There is a wealth of info on GSXR forks, there is info detailing the dimensional differences between the different years. Here is a site with some of that info.

http://www.svrider.com/forum/showthread.php?t=135430

I highly recommend the swap. It is awesome.

I had about a grand in the swap, including the Brembo RCS master cylinder and having the forks re-valved/sprung. I think I paid $600 for all the GSXR front end parts.

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Thank you so much! This is very helpful. I'm looking at an 08-09 GSXR 750 front end right now on Ebay, which is tempting me.

 

Did you have any issues adapting the steering stem? You say you used tapered bearing from a DRZ400, did those fit into the Guzzi's steering neck tube's bearing races as is? Or did you have to make shims, or otherwise have to machine them to fit? I assume you re-sprung and re-valved the forks just to have fresh guts. Was there any other reason for it?

 

If/when I do this, it will be over the winter, so I have time to sort it all out. I want to ride her before I start taking her apart ;)

 

Thanks again!

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Great link, thanks. We even get to choose the color of the forks! Much to think about before deciding if I respring / revalve my 03 lm.

 

GM, you've posted often about front suspension stuff, I wonder if there is a role for a " sticky" with your accumulated suspension knowledge?

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Thank you so much! This is very helpful. I'm looking at an 08-09 GSXR 750 front end right now on Ebay, which is tempting me.

 

Did you have any issues adapting the steering stem? You say you used tapered bearing from a DRZ400, did those fit into the Guzzi's steering neck tube's bearing races as is? Or did you have to make shims, or otherwise have to machine them to fit? I assume you re-sprung and re-valved the forks just to have fresh guts. Was there any other reason for it?

 

If/when I do this, it will be over the winter, so I have time to sort it all out. I want to ride her before I start taking her apart ;)

 

Thanks again!

The outer diameter of the DRZ tapered bearings is the same as the outer diameter of the original Daytona bearings. I would bet a dollar the V11 bearings are the same outer diameter of the Daytona bearings. And as that law of physics goes, if they are both equal to the same thing they are equal to each other.

I did not have to change out the outer bearing races, it would have worked with the original bearing outer races. But the original bearing races on my Daytona were old so I swapped them as well. The DRZ bearing races fit it the Guzzi steering head just like they should. The DRZ steering stem is the same diameter as the GSXR steering stem. As I recall the dimensions are 30mm(edited for correctness) inner and 52 mm outer. But I would/should recheck that. I'll see if I can find my notes.

The steering stem for the GSXR was a little longer the the Guzzi stem. I used a spacer to fill in the difference. As I recall it was like a 1/4". I put the spacer at the top, in hind sight I wish I had put the spacer at the bottom, under the lower bearing on the steering stem. The big difference between the older Guzzi forks and newer sportbike forks is length. The newer forks are shorter. Putting the spacer under the lower bearing on the GSXR steering stem would have meant the GSXR forks would have been dropped slightly in relation to the Guzzi's frame, making them seem longer then they are. Measure and see what you need before you do it. Once I had the bearing on the stem it was too much trouble to get it back off without damaging it. If I replace the bearing I will move the spacer. Along the lines of fork length, you will see that the different versions are different lengths. You want the longer ones. Plus, they make extended caps for some versions. The '06-'07 750/600 forks I mentioned are both longer and they make an extended cap for them. There are other options as well, research the options before you buy. The one I went with did not offer an extended fork cap. The ones I am using for my Aprilia XV roadracer project do.

I had the forks re-sprung and valved for a couple reasons. First, they were ebay forks and I did not know if they were even straight. Second, the springs were too light for a bike as heavy as the Guzzi. And third, if you make that big a change to the spring rate the odds are the valving is not going to be correct, unless it was way wrong before. Plus, it is not that expensive to have done.

Great link, thanks. We even get to choose the color of the forks! Much to think about before deciding if I respring / revalve my 03 lm. GM, you've posted often about front suspension stuff, I wonder if there is a role for a " sticky" with your accumulated suspension knowledge?
I don't know about a "sticky", but I am happy to share what I know.

I don't think the stock Guzzi forks are that bad (not counting the ohlins bikes, there is a reason why they are so popular), but they do have some issues. You can live with them the way they are. You can pay someone to resolve the issues. Or you can upgrade the whole package. I like the upgrade route as you also get better brakes and a lighter wheel. A lighter wheel makes a massive difference to handling. Better brakes speak for themselves.

 

I hope this helps. Let me know if you have any questions about what I said or what I didn't say.

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Oh, they also make top triple clamps for some GSXR's that have handle bar mounts. That is what I went with for my Daytona (yes, I converted it to handle bars, I am older and need comfort). That would be a consideration as well. Not all of them have that option, it is mainly the stunt bike people that determine whether or not handle bar clamps are available for that model or not.

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"The outer diameter of the DRZ tapered bearings is the same as the outer diameter of the original Daytona bearings. I would bet a dollar the V11 bearings are the same outer diameter of the Daytona bearings. And as that law of physics goes, if they are both equal to the same thing they are equal to each other.

I did not have to change out the outer bearing races, it would have worked with the original bearing outer races. But the original bearing races on my Daytona were old so I swapped them as well. The DRZ bearing races fit it the Guzzi steering head just like they should. The DRZ steering stem is the same diameter as the GSXR steering stem."

 

Well that certainly makes things a lot easier! Looking at the chassis diagrams in the service manual, it does appear like the diameter of the bearing seats in the steering neck tube are 52mm... This has been of invaluable help. Thank you again and agin. I hope you don't mind if I pester you with more questions as they come up!

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Okay, I think my 25mm/52mm bearing dimensions was wrong. I think the correct answer is 30mm/52mm.

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So, looking at the specs, the 08-09 GSXR forks are about 12mm shorter than the ones on my v11. Is that significant enough of a difference to warrant the use of extender caps? How much would that difference affect handling?

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Many people drop the forks on their later model V11s to get the steering back towards where the early model red frame ones are. They raked out the V11 a degree or so as people complained the bike steered too quickly. Everything is relative.....

Anyway, people often drop the front end 10 - 15 mm, so I would say that should not be an issue, but it should make your bike steer faster. You may prefer that you may not. If it were me I would try it and see what you think.

Something else that enters into it in a positive way is the trail. The GSXR forks have less offset than the Guzzi forks and as such the GSXR forks will have more trail than the Guzzi forks at the same angle. More trail, as long as it is not too much trail, is a good thing and helps with stability and feel.

But knowing the extender caps are available if you should decide you need them is a good thing.

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You rock.

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So, another question came to mind. What did you end up doing about the speedo? Is the Guzzi speedo drive compatible with the GSXR wheel/axle? Or did you have to use the GSXR speedo drive? Were you able to keep the Guzzi instruments?

 

EDIT: never mind. Looking at the service manual I now see that the speedo is driven off the gearbox. Pretty cool! I'm used to my old Hondas and Yamaha which have the speedo drive off the front wheel... One less thing to worry about.

 

As far as the brake lines go, do the radial calipers require special lines, or will the existing lines work?

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