GRiSO roller tappet conversion - Denver, CO

Hey all,

I've been wanting a Tenni green GRiSO ever since my buddy had a GRiSO about 10yrs ago.

I finally have the opportunity to get a 2011 GRiSO tenni green with 11k miles on the clock. This bike has been very well cared for, however, it never got the roller tappet treatment.

I've been doing my due diligence and reading up on the topic. I understand it's not a matter of if it will fail, but when. I get it.

My question is, has anyone in the Denver, CO area had this done? I've spoken to both MG dealers here, and quite honestly I'm not getting a warm and fuzzy feeling from them. The one dealer (actually both) didn't even know about the problem. They both couldn't really quote me labor since they aren't super experienced with the kit available.

So that leaves me with checking out independent shops in the area as well. I'm not getting a ton of confident vibes my bike would be in good hands of a competent and meticulous tech to do the job.

I've always wanted this color GRiSO, I have the opportunity, but I'm concerned I'll be left with either a hassle on my hands....or a repair that will end up costing way more than I'm hoping.

Does anyone have any input or know someone in the Denver, CO area they would trust doing this work?

I appreciate it. Thanks

A friend from Denver brought his EV all the way to GA for me to tune, got the same feeling about the shops out there. He was going to SC so he stopped here.
Guzzi supplies parts & you labor. Takes me an Hr on each side for most, yours needs more time.
I can't believe they know nothing. Been doing these now 10yrs. BMW guys that don't like Guzzi's is what I've heard about the area.

Yea it's been a struggle. The two MG dealers here just aren't giving me the vibe I was hoping.

I guess I will call a couple independent shops tomorrow. I just don't want to be in a situation where I can't get the work done. I'm going to have to 'trust' someone at some point here, locally.

While the actual rollerisation shouldn’t be a big deal, especially on a 2011 model which should require an ‘A’ kit, it would be the remapping and tuning afterwards that would cause me to worry.

How confident are you in your own abilities? You could always DIY.

I'm pretty mechanically inclined but something about this kit is just telling me to stay in my lane and have a skilled tech do it.

From what I've read, I would need the 'B' kit that doesn't require head removal.

How big of an issue is remapping this bike? Isn't that all software related that can be done via computer etc?

If the bike is an ‘11 it should be an ‘A’ kit but it’s really easy to establish simply by whipping off a rocker cover. Flip the plug cap up from underneath, don’t pull it from the top, then lift the rocker cover. If the plug tube is sealed by a circular gasket of the same cross section as the rocker cover gasket itself it’s an ‘A’ kit engine. If the plug tube has an actual ‘Tube’ that pokes through the rocker carrier casting and seals with an o-ring in a groove in the rocker cover itself then it’s an earlier ‘B’ kit engine. There are a couple of other identifiers as well but that one is easy and definitive.

As stated, if it is a 2011 it will be an ‘A’ kit bike.

Ok, I will definitely have that checked before I order a kit. Right now I'm just trying to find a tech to install it, and make sure it's in good hands.

Is the remapping required when doing the kit?

With a 2011, if you are sticking with the factory map? No, as by that time they were all running the final iteration factory map. You can just clear the trims and go. It will need a TB balance though and that requires you to be able to recalibrate the TPS. It is also vital that you don’t allow someone who doesn’t know what they are doing to screw around with the throttlebodies.

The little nuisances are scaring me more and more. Ugh.

I wish there was a resident Guzzi GRiSO guru in my area.

My one MG dealer said they could do it, but it would have to be in the fall when things slow down. I just don't know if they know all these little work around/tricks. They are all about selling and doing preventative service on new bikes.

There used to be a MG dealer in Ft. Collins. I understand they were bought out or absorbed by a larger dealer. Perhaps they still have someone who knows about the rollerization.

rick pope wrote:

There used to be a MG dealer in Ft. Collins.  I understand they were bought out or absorbed by a larger dealer.  Perhaps they still have someone who knows about the rollerization.

That would be ACE's. They didn't really know about the rollerization either, had to call a couple times to finally get a concrete answer. They said to get the kit, and they would install it but couldn't tell me how much it would cost (hours). :/

Pete Roper wrote:

If the bike is an ‘11 it should be an ‘A’ kit but it’s really easy to establish simply by whipping off a rocker cover. Flip the plug cap up from underneath, don’t pull it from the top, then lift the rocker cover. If the plug tube is sealed by a circular gasket of the same cross section as the rocker cover gasket itself it’s an ‘A’ kit engine. If the plug tube has an actual ‘Tube’ that pokes through the rocker carrier casting and seals with an o-ring in a groove in the rocker cover itself then it’s an earlier ‘B’ kit engine. There are a couple of other identifiers as well but that one is easy and definitive.

As stated, if it is a 2011 it will be an ‘A’ kit bike.

Pete - I've been told if I go with the 'newer kit' that I would need new valve covers as well. I've not seen anyone mention this when doing the conversion. This was stated to me directly from GT Motocycles. They mentioned there being an 'older kit' which was more involved, and then a 'newer kit' which required valve covers.

It starts to get a little convoluted on what I need. I haven't confirmed 100% yet if whomever I have do the install is going to order the parts, or if I need to. If I need to, I want to be 100% sure on what to get. Thanks for all your input and help!

That is because the proprietor of GT motorcycles doesn’t know what the fuck he is talking about.

Read my ‘Definitive guide’ pegged on this board. It covers the issue comprehensively. If you have further questions? Fire away. I’m currently helping another bloke with a Stelvio from somewhere in the US and he was telling me the same bullshit story about needing to change rocker covers! I was wondering which particular Rhodes Scholar had come up with that cock and bull story. Can’t say I’m surprised.

Pete Roper wrote:

That is because the proprietor of GT motorcycles doesn’t know what the fuck he is talking about.

Read my ‘Definitive guide’ pegged on this board. It covers the issue comprehensively. If you have further questions? Fire away. I’m currently helping another bloke with a Stelvio from somewhere in the US and he was telling me the same bullshit story about needing to change rocker covers! I was wondering which particular Rhodes Scholar had come up with that cock and bull story. Can’t say I’m surprised.

Exactly what I was thinking! I was like...oookkkk? And why do I need new covers? They couldn't answer that.

I also don't like the fact I can't even call them to discuss a potential order. It's all email, which drives me a little crazy.

I'm just going to order from AF1 at this point. Sounds like I just need the 'A' kit like you mentioned (thanks for confirming). Is there anything else I should grab from them when I call tomorrow? I just want to make sure I get everything I need, so I can supply them with the parts.

I FINALLY spoke with a local shop here in Denver who is actually familiar with the roller tappet conversion. It was a breath of fresh air - looks like I found my shop.

Again, thank you so much for the help. I've gotten more clarification from you than I have from calling BOTH local MG dealers here in town.

probably wouldn't hurt to print out Pete's guide and take it to them. I did that with my drive shaft when the pinion shaft seal came lose and I didn't feel comfortable digging into it myself. I had 11 pages with pictures and I know the shop/MG dealer looked at it........................

JohnA wrote:

probably wouldn't hurt to print out Pete's guide and take it to them. I did that with my drive shaft when the pinion shaft seal came lose and I didn't feel comfortable digging into it myself. I had 11 pages with pictures and I know the shop/MG dealer looked at it........................

Good call - thank you!

Pete Roper wrote:

If the bike is an ‘11 it should be an ‘A’ kit but it’s really easy to establish simply by whipping off a rocker cover. Flip the plug cap up from underneath, don’t pull it from the top, then lift the rocker cover. If the plug tube is sealed by a circular gasket of the same cross section as the rocker cover gasket itself it’s an ‘A’ kit engine. If the plug tube has an actual ‘Tube’ that pokes through the rocker carrier casting and seals with an o-ring in a groove in the rocker cover itself then it’s an earlier ‘B’ kit engine. There are a couple of other identifiers as well but that one is easy and definitive.

As stated, if it is a 2011 it will be an ‘A’ kit bike.

I had the seller pull off the cover to take some pics. This is what he had sent me - hoping this can conclude if it's an 'A' or 'B' kit.

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Nope. It’s NOT a 2011 model year bike. You can tell this from the fact that there is an actual *Tube* sticking up out of the rocker carrier/cambox casting, the fact that the rockers are of the earlier design and the valve lash adjusters have flat bladed screwdriver slots in them rather than hexagonal, 3mm allen key holes in them. The earlier adjusters and the rockers they go into use a coarser thread as well than the later ones.

To confirm that you need a ‘B’ kit look at he side of the head that faces into the valley of the motor. If it has a drill mark, (Shiny dot in the paint.) adjacent to the manufacturing date stamp then it will need a ‘B’ kit. If there is no drill mark it is an early, ‘C’ kit bike.

My guess is it will probably be a 2010 bike sold as a 2011 so it will probably be a ‘B’ kit bike. We need to confirm this though before you order parts.

rick pope wrote:

There used to be a MG dealer in Ft. Collins.  I understand they were bought out or absorbed by a larger dealer.  Perhaps they still have someone who knows about the rollerization.

Just talked to MG TechRep here and said the tech there in back should know at Aces if he's not been replaced.
He also said the campaign is over for payment of kits.
Glad you found someone that knows how.

It's a long shot, but you might call Cadre Cycle in Cincinnati, and ask them if they know of a mechanic in your area whos' knowledgeable and willing. Enzo seems to have connections, as does Tim, the guy behind the counter. Tell 'em I sent you.

Thinking about the whole ‘Replace the rocker covers’ thing? That may, indirectly, have something to do with me.

Way back when when the flat tappet fiasco was finally acknowledged by the factory I was still posting on that board. If memory serves I think I may of said that because of pricing at the time it might be better to use an ‘A’ kit and swap the rocker covers rather than buy a ‘C’ kit because at that time an ‘A’ kit, plus a late model rocker cover and the *extra* bits needed to make up the heads to spec actually came out cheaper than buying a ‘C’ kit in certain markets due to a huge discrepancy between the cost of early and late type rocker covers.

Since then many things have changed, and not just prices! I discovered, sometimes the hard way, that there are other differences between the ‘A’ and ‘D’ type camboxes and the ‘B’ and ‘C’ type camboxes and the machining of the heads on which they fit. Now I’ve publicised this widely and on many forums and will always answer queries from anyone who wants to contact me for clarification.

Believe me, I’ve dedicated a decade and a half of my life trying to understand the CARC bikes and counter bullshit about them and while I feel it is probably a losing battle in the long run I can still, at the moment, try to counter the ignorant bullshit that seems to pervade the internet about what was one of the best series of machines to ever come out of Mandello.

Seems like a lot of grief you’re going through there in Rockies. Amazes me the limited number of wrenches willing to take the time to understand this bike.

I can tell you this though, to Pete’s last point in the prior post: once dialed in you will be so very happy to own this machine. A singing 1200 8V GRiSO is a gem. Good luck.


Here in Indy there’s a ‘metric only’ shop. states NO HARLEYS (bold for Indiana). He’s on Gasoline Alley near the speedway. His whole business model revolves around keeping old Japanese bikes running, it would seem. He bought an original 09 in great shape. Contacted Guzzi. Got the kit. Did the job. Sold the bike to local enthusiast who rides it often. Even loaned it out to me prior to my own purchase. The bike is wonderful. My point being that a good mechanic who takes his time and digests the available info can do this job. Why couldn’t more? No sacrificed chickens. No translators. Befuddling.


I hope it works out for you.

Pete Roper wrote:

Nope. It’s NOT a 2011 model year bike. You can tell this from the fact that there is an actual *Tube* sticking up out of the rocker carrier/cambox casting, the fact that the rockers are of the earlier design and the valve lash adjusters have flat bladed screwdriver slots in them rather than hexagonal, 3mm allen key holes in them. The earlier adjusters and the rockers they go into use a coarser thread as well than the later ones.

To confirm that you need a ‘B’ kit look at he side of the head that faces into the valley of the motor. If it has a drill mark, (Shiny dot in the paint.) adjacent to the manufacturing date stamp then it will need a ‘B’ kit. If there is no drill mark it is an early, ‘C’ kit bike.

My guess is it will probably be a 2010 bike sold as a 2011 so it will probably be a ‘B’ kit bike. We need to confirm this though before you order parts.

You sir, have been an extreme help! I had the seller take a picture (the best he could). Looks like I need the 'B' kit just like you stated. Whew, nice to get that out of the way. I will be calling AF1 today to get price and lead time.

I shared your rollerisation guide/write up with the owner of the shop I've been in contact with. He was very thankful for that. He is the first tech/shop I've spoken to that is actually willing to do his research before taking on this conversion. He was aware of it - but is also open ears to any tips or tricks to make sure all goes smoothly.

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kidsmoke wrote:

Seems like a lot of grief you’re going through there in Rockies. Amazes me  the limited number of wrenches willing to take the time to understand this bike.

I can tell you this though, to Pete’s last point in the prior post: once dialed in you will be so very happy to own this machine. A singing 1200 8V GRiSO is a gem. Good luck.


Here in Indy there’s a ‘metric only’ shop. states NO HARLEYS (bold for Indiana). He’s on Gasoline Alley near the speedway. His whole business model revolves around keeping old Japanese bikes running, it would seem. He bought an original 09 in great shape. Contacted Guzzi. Got the kit. Did the job. Sold the bike to local enthusiast who rides it often. Even loaned it out to me prior to my own purchase. The bike is wonderful. My point being that a good mechanic who takes his time and digests the available info can do this job. Why couldn’t more?  No sacrificed chickens. No translators. Befuddling.


I hope it works out for you.

Thanks for the kind words - I actually thrive on doing my research and making a plan come to fruition. I've always thought the GRiSO was one of the most sexy bikes I've laid eyes on. 10 years ago my good friend had a silver 2013 GRiSO and I always lusted after it. I was riding a tricked out Harley Blackline at the time. He showed me the Tenni green version of the GRiSO and I immediately fell in love.

Fast foward 10 years and here I am picking one up. I always told myself, if I found a very clean example for the right price, I'd get it. I didn't know anything about the roller vs tappet fiasco but I am learning as I go. I am excited to get this bike and keep it from grenading, and having a sweet bike for years to come.

Your comments about finding a good wrench have never been more true. I swear, the dealers here in Colorado are more interested in selling a new bike and having a customer for preventative maintenance. I had to ask 3 different times to finally get a concrete answer on whether they would do the conversion on the GRiSO. It just didn't leave me feeling comfortable at all with them. Oh well.

The shop I'm going to have do it is actually an independent shop. They specialize in vingtage motorcycles but also have a deep understanding and love for Japanese and European bikes. They just seem like they take pride in their work in general, and that is half the battle in my opinion. This conversion can't be rocket science, but I want to make sure whoever lays hands on it, treats it like it's their own.

Also read up on what is advisable WRT swingarm bearings, shock linkage bearings and the sump spacer gasket.