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I take a certain trip a few times per year and i do 90 MPH most of the way to get there before my old man's body gives out on me. Plus i'm just an impatient sort.:smile2: At 90 my Tbird is barely breathing, but i am contemplating a T120 and was wondering how fast the engine is spinning at 90 MPH should i decide to use that for my trips. Anyone know?
 

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you need to specify exactly what year and model machine you are riding in order to obtain the gear ratios.

i ride way-old T120s, and based on the gears and wheels in my machine, my 1965 T120 is doing 4850 at 90.3 mph in 4th.
 

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I take a certain trip a few times per year and i do 90 MPH most of the way to get there before my old man's body gives out on me. Plus i'm just an impatient sort.:smile2: At 90 my Tbird is barely breathing, but i am contemplating a T120 and was wondering how fast the engine is spinning at 90 MPH should i decide to use that for my trips. Anyone know?
I don't know the RPMs but 90mph on a new T120 is easy, as long as the wind doesn't tire you out or you have a windshield. One thing about the new bikes, is that 6 gear really keeps the RPM's in check

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This is the water cooled forum so i thought it should be obvious. The current T120.

you need to specify exactly what year and model machine you are riding in order to obtain the gear ratios.

i ride way-old T120s, and based on the gears and wheels in my machine, my 1965 T120 is doing 4850 at 90.3 mph in 4th.
 

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An even 4,000 RPM on my T120 is 88 MPH indicated. Noticed this the day I took delivery of the bike. Triumph recommended that 4,000 RPM not be exceeded during initial break-in. This was really easy to stick to as I went sailing down the superslab on the way home.
 

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Discussion Starter #6
I don't know the RPMs but 90mph on a new T120 is easy, as long as the wind doesn't tire you out or you have a windshield. One thing about the new bikes, is that 6 gear really keeps the RPM's in check

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So 90 MPH for most of a 7 hour rides seems easy for it? If anyone knows the RPMs i'd still be interested. I found a video review and shots of the cluster as he was riding seemed to indicate 70 MPH and 4000 RPMs. Seems kinda high given i'm talking 90MPH. I had a 05' speedmaster that was at 4k at 70 MPH and at 90 i think it was at 5500 which is rather high given the redline. I would think the 120 would be geared higher then 4k RPMs at 70, tho maybe the guy was in 5th, i dunno. But i wouldn't think so, as i have a thunderbird that is at 3k at 80 and yet i typically don't cruise at 70 in any gear but 6th. Why would you? Twisteis, yeah, but highway cruising at 70 i would think anyone would use top gear unless passing.
 

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On a 2018 T120 less than 5000 rpm, I changed to a 42 tooth rear sprocket from the 37, so mine rev's higher but I was still below 6000 rpm.
Before the sprocket change the 4000 rpm limit of breakin, was about 80 mph

If your are under redline it should be fine. You will need a windscreen of some sort, 90 on a naked bike is hard work after 30 minutes.
 

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@vistavette would use his K1600GTL for that ride because the cruise will hold it north of 120 all day long and there's a nice fairing to hide behind :grin2:
Ha! You read my mind. I was just going to post the same.

90 on my '16 T120 (I sold it recently) was no sweat for the bike, but 7 hrs at 90 on anything is hard on a machine.

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Well, i have no windshield on my Tbird and i'm 66 in a few days and just got back from that trip a couple weeks ago. Yeah, it beats ya up a bit, but i grew up riding w/o windshields and i can handle it. The bike can too, as at 90 MPH it's only about 1/2 way to redline. In fact 90 is the low end, i have it to 95-100 much of the time only dropping down to 80-85 thru major metro areas where the HP is watching. (and watching my rear-views like a hawk.

Anyways, i do want to be able to stay at 90 the majority of the7 hour ride w/o beating the engine up. If the T120 isn't up to that i'll have to rethink what i wanna do.
 

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Well, i have no windshield on my Tbird and i'm 66 in a few days and just got back from that trip a couple weeks ago. Yeah, it beats ya up a bit, but i grew up riding w/o windshields and i can handle it. The bike can too, as at 90 MPH it's only about 1/2 way to redline. In fact 90 is the low end, i have it to 95-100 much of the time only dropping down to 80-85 thru major metro areas where the HP is watching. (and watching my rear-views like a hawk.



Anyways, i do want to be able to stay at 90 the majority of the7 hour ride w/o beating the engine up. If the T120 isn't up to that i'll have to rethink what i wanna do.


I don’t think you will beat up the engine. I’m riding a ‘17 T100 for 18,000 in the last 20 months. My daily commute on the 405 slab in LA has me doing 80-85. My bike is a five speed so my RPM’s are higher(we share the same gear ratios on 1-5 absent the sixth gear).

I do push it and it’s running like a champ. I have done a couple of quick trips from LA to San Diego and find that on the longer, high speed rides I stretch out by riding with my feet on the pillion pegs. I put a tank bag on the top and filled it with foam and I and put pressure on it from the abdomen, getting my head down lower in the slip stream of the headlight/front end while relieving the pressure on my lower back.

My favorite (favorite) part of the highway trips is my Triumph cruise control. I recently snapped one up on eBay for a song, installed it the day it arrived and I can’t say enough good things about it.

Throttle -by-wire CC is the best since it controls the speed at the throttle bodies. The uphill/downhill speeds are super consistent. It also enables you to switch up hand positions during those long trips eliminating hand and shoulder fatigue.

Happy travels!



2017 T100- OHLINS TR 634/FKS 215, LSL Flat Tracker handlebars, Triumph Cruise Control, Booster Plug, STS (Smart Turn System)auto turn signal cancelation, Modified comfort seat with Supracor, Chrome Grab Rail, Triumph Barrel Style Hand Grips, Aluminum Oil Filler Cap, Cibie 82240 Light unit, Triumph Center Stand
 

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This is the water cooled forum so i thought it should be obvious. The current T120.
it's not hard to do. it's the same whether your machine has a radiator or not.

get your primary ratio from your shop manual, multiply by your final drive ratio, and then by a sample rpm to get rear wheel rpm.

take that rear wheel rpm and multiply by the circumference of your rear wheel and your final gearbox internal ratio. older british machines are 1:1, i have no idea what yours might be. they differ from model to model.

then divide by whatever units you used to measure your rear wheel. if you used inches, divide by 12, then 5280 to get miles per minute.

multiply by 60 to get miles per hour at your sample rpm.

substitute different rpms until you get one that works out close to 90 mph, and you have your answer.
 

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it's not hard to do. it's the same whether your machine has a radiator or not.

get your primary ratio from your shop manual, multiply by your final drive ratio, and then by a sample rpm to get rear wheel rpm.

take that rear wheel rpm and multiply by the circumference of your rear wheel and your final gearbox internal ratio. older british machines are 1:1, i have no idea what yours might be. they differ from model to model.

then divide by whatever units you used to measure your rear wheel. if you used inches, divide by 12, then 5280 to get miles per minute.

multiply by 60 to get miles per hour at your sample rpm.

substitute different rpms until you get one that works out close to 90 mph, and you have your answer.
Can you run that past me again in metric:wink2:
 

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On my ride today with stock gearing, 90mph indicated was just a hair over 4k RPM. 4100 if I had to take a stab at it(close to what is indicated on gearing commander above).

The T120 will chug along effortlessly at this speed, it's the rider who generally gets tired first, but that's an entirely different dilemma to solve.
 
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