How to replace your rotten Griso turn signal stems with better Aprilia ones

[Moto]

Griso turn signal stems fail all too soon, without warning. Here is a cheap, quality replacement.

The Aprilia turn signal stems sold by AF1 at four for $5.99, can easily be adapted. (This works out to $3.36 each, with shipping, if one set is all you order.) The OEM Griso turn signals are over $34 each, plus shipping, at MGCycle, and of course Griso replacement stems aren't sold separately. So, big savings come from using the Aprilias.

The Aprilia stems are rounded in cross section and about a half inch longer. Here's how one looks installed on my Griso:



You need a  fine saw and a drill, and maybe a chisel, to do the modification, which takes a little over 5 minutes each once you've done the first one. I used a fine dovetail saw, a 1/4-inch brad-point drill bit in a drill press, and a 1/4-inch woodworking chisel.

To remove the turn signal, unscrew the lens cover screw, and carefully remove the two covers and the reflector/bulb assembly. The outer cover is held in place on its other end by a plastic tab, and you must be careful not to break that as you rotate and wiggle the assembly out. Unclip the two wires from the reflector assembly, remove the assembly, unbolt the the old stem, and pull it over the wires.

Here is a side view of three stems, from left to right: original Griso; Aprilia with some material cut away; unmodified Aprilia:



You put a stem in the vise, and start cutting downward to match the existing cutaway's plane:



Here is a photo of a modified Aprilia stem, with the original Griso one below:



Note carefully that you need to leave a 2-3mm (or so) lip between the bottom of the extended plane and the first rib of the stem. [EDIT: I found that a lip of 2mm made it easier to install one of my covers; originally I said 3mm should be the goal.] This is what the turn signal housing will rest against. The location of the 1/4-inch hole, which is about 1/8-inch deep, is also important. It allows room for the plastic tab that holds one end of the outer lens cover in position. Once you have the plane cut, you can insert the stem in the housing to see where the hole needs to be. Once cut, you should probably clean up the sides of the hole,  and even square it out, with a 1/4-inch chisel or a knife, just to make it easier to get the tab into it during final assembly.

Final assembly is the hardest part. First, the Aprilia stem has a narrower hole, and getting the two wires through it can be like pushing fishing line through a throttle cable housing! The two little end connectors can't pass through the hole at the same time, so a good trick is to wind one of the wires tightly around the other, while keeping the second wire straight, so that the two connectors are no longer side-by-side:



The last challenge is jostling the reflector and two covers together to get them seated with the plastic tab hooked into the housing. This is where you thank yourself for having carefully observed how the whole thing came apart. No doubt this patented monstrosity is assembled by some cunning robot, saving a penny for a second screw.

I'm doing all four of my stems, at a total cost of $13.50 or so, so that I can stop worrying if one is going to fail on my next long trip. The AF1 web page, http://www.af1racing.com/store/Scripts/prodView.asp?idproduct=57075 says the replacements are more durable than the OEM's. The bags they come in show they are actually Triumph parts (Triumph part number T2701039, Indicator Stem Kit, made in United Kingdom). The web page also has a video showing how the Aprilia turn signals come apart and go back together, apparently a bit easier than mine.

Moto

[Pisano]

Thanks for documenting this.

Appreciated

Norm F.

[not-fishing]

Thanks, I don't need them now on my 07 Griso but having spent time with the Boy Scouts I think I'll buy a set and mod them to be ready.

Mark

[Pisano]

Hi Moto,
From the picture it looks like the Griso spigots have a larger outside diameter than the Aprilla.



photo hosting ebay


is this the case?  if so do you think there may be potential for movement over time since the Aprilla spigots may not completely fill the hole in the headlight bracket?

Thanks

Norm F.

[Moto]

Hi Moto,
From the picture it looks like the Griso spigots have a larger outside diameter than the Aprilla.



photo hosting ebay


is this the case?  if so do you think there may be potential for movement over time since the Aprilla spigots may not completely fill the hole in the headlight bracket?

Thanks

Norm F.

Potential, sure. But I doubt it will happen since the attachment bolt in the back snugs everything down. There is a pretty good bearing surface, I think, between the stem and the mounting location. If I have a problem with that, I'll be sure to post about it.

EDIT: I should have mentioned that the Aprilia/Triumph stems have nice brass inserts that surround the attachment bolt and form a surface that contacts the mount. This means the bolt can tighten up on the brass insert instead of merely compressing rubber, as is the case with the OEM Griso item. Class act, those Brits. (It also is notable that Triumph provides replacement stems, while Aprilia/Guzzi/Piaggio don't; another classy move.)

Moto

[Bulldog9]

ANyone have the part number? I have 2 broken mounts om the Griso, and NEW TS are $60. Cant find this part in the AF1 catalog, not sure which bike they are off. Or anyone have another alternative? I like the OEM TS, but have JB welded them several times..... Time to get straight.  TIA

[Motormike]

I've had two Griso turn signals I've had to replace due to old age (the plastic, not me!).  Still, it would cost me more in special tools to replicate your repair than to buy a NOS Griso turn signal.  I have found a dab of JB weld will hold the broken pieces together for quite a while.

[moto]

ANyone have the part number? I have 2 broken mounts om the Griso, and NEW TS are $60. Cant find this part in the AF1 catalog, not sure which bike they are off. Or anyone have another alternative? I like the OEM TS, but have JB welded them several times..... Time to get straight.  TIA

I looked three or four years after my original posting and couldn't find either the Aprilia part nor the Triumph one. Too bad.

[Bulldog9]

I looked three or four years after my original posting and couldn't find either the Aprilia part nor the Triumph one. Too bad.

Looks like I'm continuing to put the kids of the guys at AF1 through college. 

[moto]

Some googling led me to these possibilities:

$16.12 for a pair on ebay. Search for:

Triumph Daytona 600, 650 & 675 Indicator Stalks Stems (Pair) - NEW

Or a set of four for about $50, as Triumph part number t2701039.

I am more confident in the set of four from triumph, than in the pair from eBay. I found a discussion board that linked my Aprilia part number (57075) to the triumph kit part number, but only followed the motorcycle model reference to get to the eBay option. The eBay option does look right in the small photo. Hope this works.

EDIT: I reread one of my earlier posts and noticed that the triumph part number appears there, so it's the right one.

[PJPR01]

Unfortunately I have 1 Griso turn signal to repair as well after my latest trip to Wisconsin, my replacement just came from MG cycle yesterday.  This is a cool trick though...wish I had seen it a few years ago.

[Bulldog9]

Some googling led me to these possibilities:

$16.12 for a pair on ebay. Search for:

Triumph Daytona 600, 650 & 675 Indicator Stalks Stems (Pair) - NEW

Or a set of four for about $50, as Triumph part number t2701039.

I am more confident in the set of four from triumph, than in the pair from eBay. I found a discussion board that linked my Aprilia part number (57075) to the triumph kit part number, but only followed the motorcycle model reference to get to the eBay option. The eBay option does look right in the small photo. Hope this works.

EDIT: I reread one of my earlier posts and noticed that the triumph part number appears there, so it's the right one.

I bit the Bullet and just bought two from AF1 Racing. 1/2 price from MG Cycle, but a 3-4 week wait. Will put them on as a winter project. JB Weld once again for now.  I hate being Anal with things, but gotta keep the bikes right. 

[moto]

Since I see my original posting has been read more than 4000 (!) times I think I should clarify that the replacement stems were Triumph items, and not Aprilia parts. The 57075 "Aprilia number" must have been AR1's af1racing.com's stock number (SKU) for the Triumph part.

My installed stems are still very stable and look brand new after seven years and 5000 miles.





At $50 the kit is probably still a good deal compared to the price of four new turn signals. It should be available at any Triumph dealer under part number T2701039. Don't forget the stems have to be modified as I described in the first post.

[red stripeguz]

Funny thing is, since the original post, AF1 has added Triumph to their mix of bikes available, so you could order the Triumph part from them

[Ed / AF1 Racing]

way, way back in the day Triumph issued a recall for the floppy signal arms.  They used the same signals as APR / MG.   They had a $6-8 recall repair kit that we got for all the Aprilia Tuonos and Grisos.  Sold a ton of them.       Aprilia/MG never made it a recall, and would just replace it if you had warranty. 

The signals shortly after got updated part #s to not flop by looking at them.

Triumph ended their recall and then the part got 10x more expensive soon after.  It became cheaper to buy the new signals. 

We can still get them as a Triumph dealer direct now, but its like $50/ 4 pack and not needed on any new turn signals.
https://www.af1racing.com/LST2701039-Replacement-Turn-Signal-Stalk---FOUR-PACK

[Tom]

I found a bunch that would work from Amazon.  🤷‍♂️

[Ncdan]

This issue has came up several times over the years.
When it came up last year there was a member here that was willing to experiment with making them on a 3D printer. I needed replacements for my 02 Stone at the time and sent him one to use as a pattern. He sent me a couple in return. They needed a little widdling with a razor knife to dress up edges but functioned as they should have.
The rubber was harder that the originals but was tough as nails.
At the time he was willing to produce them and offer to members at a reasonable price.
If interested one can do a search and follow up with him.

[Bulldog9]

way, way back in the day Triumph issued a recall for the floppy signal arms.  They used the same signals as APR / MG.   They had a $6-8 recall repair kit that we got for all the Aprilia Tuonos and Grisos.  Sold a ton of them.       Aprilia/MG never made it a recall, and would just replace it if you had warranty. 

The signals shortly after got updated part #s to not flop by looking at them.

Triumph ended their recall and then the part got 10x more expensive soon after.  It became cheaper to buy the new signals. 

We can still get them as a Triumph dealer direct now, but its like $50/ 4 pack and not needed on any new turn signals.
https://www.af1racing.com/LST2701039-Replacement-Turn-Signal-Stalk---FOUR-PACK

Ed, THANKS for this. I just cancelled the two turn signals I had on order and added these.

[moto]

Ed, THANKS for this. I just cancelled the two turn signals I had on order and added these.

You'll find instructions for modifying them for the Griso in my original post.

[Bulldog9]

You'll find instructions for modifying them for the Griso in my original post.

Thanks, already have that bookmarked.

[Oca Grassa]

@Ed / AF1 ….Hey!! Nice to see a familiar user name! NorCalRSVR here from the Aprilia forum saying hi. Please say hello to Micah & Jon for me. Seems a life time ago that I dropped the New Braunfels shop for a visit….maybe because it was!! 21 years is a long time…Ciao

[Rebochi]

   I repaired mine by using heat shrink tubing and a short piece of thick tie wrap under side and under the heat shrink.  Lasted several years until I sold the bike.