The Rattle/Clank That Wasn't - V85 TT

[Xander]

Story Time

TL;DR: Cheap gas + heat + low revs + deep throttle = bad noises.

So, I bought my first Guzzi a few weeks back - a '21 V85 TT Centenario with only 3100 miles.  She's the most beautiful thing I've ever seen on 2 wheels and I admit it was a pretty (pun!) emotional purchase.


She runs great and I didn't have any worries about being stuck with a lemon, until the other day when I went out for a ride in my dense, sub-urban area.  I'd not ridden for over 20 years until I got her, so I've been taking it easy and getting my bike legs back.  On this ride, I had some road ahead, so I goosed her and heard some loud metallic rattling from the motor.    At first I was quite worried about it, but upon reading some posts about such noises, I started to think it was the conditions and my driving rather than anything really wrong with my baby.  I checked for oil level and stuff and all seemed to be in order.

I live in Tampa Bay, and as one glance at the news will tell you, it can get a bit warm.  The day I heard the clanking was a typical roaster and I'd been in some slow traffic before getting room to really go.  I don't usually focus on my dash or the rev counter much, but I do think I was too demanding in the lower RPM.  That over-zealous grip twisting and the baking heat seems to have been a bit much for the young lady.

Today I went out before the noon-day blast furnace, avoided the always-bad traffic, and even killed the engine at a long light.  I took her out on the interstate and let her revs come up before giving it the beans.  She responded like the princess she is and seemed to really love it - I know I did.  I'm very pleased to report to the wife and world that she appears to be just fine.

I do believe I learned a thing about Guzzis in general, and my bike as well.  She likes the open road and cool temperatures, and is perhaps not the best choice for the Florida summer climate rampage.  Ah, well.  It's not like I'm gonna sell her or anything.  We're just getting to know each other and it's starting to get good.

[rtbickel]

Check the bolts for the exhaust heat shields and belly pan.  The tend to work loose and cause a rattling or clanking noise.

[guzzisteve]

Too much load at too low rpm, always downshift to bring up revs then WACK IT. Have fun, It's hot here too. My V700 don't seem to mind but it's a BigBlock & has more oil.

[Xander]

Check the bolts for the exhaust heat shields and belly pan.  The tend to work loose and cause a rattling or clanking noise.

Aha, that's good to know - thanks!

Too much load at too low rpm, always downshift to bring up revs then WACK IT. Have fun, It's hot here too. My V700 don't seem to mind but it's a BigBlock & has more oil.

[nods knowingly]

[Dirk_S]

What fuel grade are you using? Ensuring the right octane level could help keep some of that away as well.

[Xander]

What fuel grade are you using? Ensuring the right octane level could help keep some of that away as well.

I use the lowest (85 87), and she seems fine on it when I'm not abusing her.

[Tkelly]

Don’t use that cheapshit.

[Xander]

Don’t use that cheapshit.

Um... why not?

[Dirk_S]

Because Guzzi tells you not to in the manual. Higher compression motors often require higher octane fuel to avoid premature ignition. Hotter days + lower octane fuel = potential pinging (predetonation). That said, I’m no expert, but it’s what I’ve gathered from reading.

[Xander]

Because Guzzi tells you not to in the manual. Higher compression motors often require higher octane fuel to avoid premature ignition. Hotter days + lower octane fuel = potential pinging (predetonation). That said, I’m no expert, but it’s what I’ve gathered from reading.

So it does!    Y'all teachin' me stuff.  I am very new to Guzzi world.  Specifically it says:

Unleaded petrol max E10 (95 RON).

95 RON translates to ~91 octane in the US.

It also says:

Compression ratio 10.5 ± 0.5 : 1

I hear a lot of fluff about higher octane being "just better" or "higher performance" or some such, when in fact it rarely makes any sense to pay more.  However, this is a case where it is in fact important.

Lesson learned!  I guess I should go ahead and read that whole manual cover to cover.

Thanks, Dirk!

[Dave Swanson]

Stick with the factory octane recommendations, you and the bike will be the better for it. 

Whenever possible I fill with non ethanol premium.  With the Puregas app (free), it finds the closest station that offers it for you, 

[Xander]

Stick with the factory octane recommendations, you and the bike will be the better for it.

Yep, I'm sold - nothing but premium from now on.

Whenever possible I fill with non ethanol premium.  With the Puregas app (free), it finds the closest station that offers it for you,

I noticed the "E10" in the manual and apparently that refers to a maximum of 10% ethanol.  I think I'll keep all the ethanol for myself - the bike will be better off without it.  I'll look into that app.  Thankfully, we have a Wawa close to home that sells ethanol-free which I also use for the generator around this time of year.

[twowings]

Also, just because it's a twin, DON'T lug it around like your Hardly Ableson buddies...this is a finely-engineered Italian machine that likes to be kept in the powerband. 

[yrunvs]

And since you bought it used I wonder if the previous owner was using 10/60 oil? With the air cooled Guzzi the thicker oil is very important on hot days.

[Xander]

And since you bought it used I wonder if the previous owner was using 10/60 oil? With the air cooled Guzzi the thicker oil is very important on hot days.

That's a very good question.  I was planning to do an all-around fluid/filter change, so that'll be covered.

Do you suggest using something thicker than 10w60?

[Vagrant]

There was a map update in late 22. Yours might not have it. If, you bought it from a Guzzi dealer, he should check it and load it free.
3500+ RPM in the first three gears as a minimum RPM and 4000+ in the last three. Both 5 & 6 are overdrive gears.
Since when did Fl. start selling 85? That's high altitude western states junk.

[yrunvs]

That's a very good question.  I was planning to do an all-around fluid/filter change, so that'll be covered.

Do you suggest using something thicker than 10w60?

No just stick to 10/60 full synth.

[Xander]

There was a map update in late 22. Yours might not have it. If, you bought it from a Guzzi dealer, he should check it and load it free.

I'll call my guy at the Guzzi dealer I bought her from.  I'm lucky they're literally right around the corner.

3500+ RPM in the first three gears as a minimum RPM and 4000+ in the last three. Both 5 & 6 are overdrive gears.

Great tip, thanks!

Since when did Fl. start selling 85? That's high altitude western states junk.

I mistypespoked.  It's 87 here.

[Huzo]

Can I have an explanation as to what an “overdrive gear” is ?

[Xander]

Can I have an explanation as to what an “overdrive gear” is ?

It just means a high gear that let's the engine run at a lower RPM.

https://en.wikipedia.org/wiki/Overdrive_(mechanics)

Correction/additional:  Back in the day, "overdrive" was a separate unit mounted to the output of a transmission, and may have referred to a planetary type gearing, but clearly I could be am wrong.   

[mondtster]

Can I have an explanation as to what an “overdrive gear” is ?

A transmission ratio of less than 1:1. In other words, the output shaft is turning faster than the input shaft.

[mondtster]

Regarding the V85TT, fuel selection, and high load knock, it seems that Guzzi has a fairly aggressive engine calibration on these engines which is probably in an effort to make the bike as competitive as it can be in the 850cc adventure bike class. When they tell you to use high octane fuel, they mean it and you may experience knock even with high octane in some conditions. It doesn't help that these engines run hot because they are in closed loop during low and mid range loads.

[Tkelly]

My 14 Stelvio runs fine on 87 but I never tried 85,even in my old 05 Grand Marquis.Saw it a lot out west,is that 15% ethanol?

[twowheeladdict]

Can I have an explanation as to what an “overdrive gear” is ?

Serious?

From the service manual.
chrome-extension://efaidnbmnnnibpcajpcglclefindmkaj/https://cadrecycle.com/manuals/technical/v85-service-manual.pdf





Both 5th and 6th are overdrive ratios.

[Xander]

My 14 Stelvio runs fine on 87 but I never tried 85,even in my old 05 Grand Marquis.Saw it a lot out west,is that 15% ethanol?

No, that was about octane.

[Xander]

...
From the service manual.
...


Both 5th and 6th are overdrive ratios.

There's me learning again.  I never knew that specific meaning of "overdrive".

[Xander]

These references to the manual make me wonder if the one I have is correct and current.  Can anyone confirm?

https://www.ezriilc.com/images/Catey/Service-Station-Manual_v85_tt.pdf

Page 25 has gear ratios.

[Xander]

...
Whenever possible I fill with non ethanol premium.  With the Puregas app (free), it finds the closest station that offers it for you,

I did some checking and ethanol-free, high-octane gas is pretty rare.  And though that app doesn't appear to have an Android version, I did find a site that seems to have good info.  For those interested:
https://www.pure-gas.org/

[ridingron]

About the gas. I live in the Orlando area so I'm aware of the heat. I run regular grade gas, I think 87 with 10% corn squeezings, from a name brand station. I've had the bike over a year and no problems so far.

[elrealistico]

I live in the Tampa area also, let's see if we can meet up sometime! Rattly heat shields or bashplates are a thing, just tighten up the screws for them. See you on the road!