990 synro 1972 road top speed

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roscommon
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Location: ireland

990 synro 1972 road top speed

Post by roscommon » Fri Oct 31, 2014 7:20 pm

Recently purchased a 990 case its about 70 mile from my house , getting crazy quotes of 350 to transport it, so I've decided to drive it home this Sunday, not bad 350 for 5 hrs of driving ! So what top speed can I expect , also a slight wobble coming from back wheel , well at least when I get home I will know what type of tractor I have bought , Q

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bedwards1966
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RE: 990 synro 1972 road top speed

Post by bedwards1966 » Sat Nov 01, 2014 1:37 am

To find out the speed you need to know the tyre size and which reductions it is fitted with.
The manual says it will be anywhere between 12.2 to 17.6 mph depending on what is fitted.

I think I'd want to investigate the wobble before setting out on a 70 mile trip, you don't want something breaking up or falling apart!

John_Allen
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Location: Cumbria UK

RE: 990 synro 1972 road top speed

Post by John_Allen » Sat Nov 01, 2014 8:02 am

I drove my 995 twenty five miles from the dealer's and, to be honest, that was too far! Although it was an interesting journey, I'd only test driven the machine in the dealer's yard and, after agreeing to buy it, he fitted PAS and a loader, which made it a very different beast. I think it took about two hours to get home (allowing for a stop to buy food and a pause when I stopped to chat with a former pupil driving his "new" Leyland tractor!)

As bedwards wrote, I'd want to be sure the wobble isn't at all serious before I set off. If nothing else, it will be a very tiring to drive. My 995 had been standing a while and the back wheels were flat-spotted: not comfy at all for about five miles!

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roscommon
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RE: 990 synro 1972 road top speed

Post by roscommon » Sat Nov 01, 2014 9:13 am

Well not sure what u mean by un comfortable or do you mean dangerious , I could easily cycle that distance so driving should be more comfortable, . however rear wheel wobble is a concern, is it possible for a wheel to come off!

Guest

RE: 990 synro 1972 road top speed

Post by Guest » Sat Nov 01, 2014 9:28 am

If it's the outer hub bearing that's causing the wobble yes, the wheel could come off, you would be better to pay to transport the tractor rather than chance it breaking down on the road and then having to pay through the nose to get it shifted off the road and recovered which will be an even more expensive way of getting it home and then it will cost you more to fix the tractor due to more possible damage caused by driving it. In attempting to drive it that distance with a known problem, with the greatest respect, you're either very brave or rather silly.

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ollek
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RE: 990 synro 1972 road top speed

Post by ollek » Sat Nov 01, 2014 9:30 am

A flat-spot on a tire means that the tyre is not round because there is a flat portion on the tyre when you start driving. It will take a long while before the tyre gets warm and the flat-spot disappears. During that time the driving is very bumpy as the tyre is not round. Not at all comfortable as the driver is bumping around in the cab when the driving speed is increased. All tractors that have been standing for a ling time with low tyre pressure will have a flat-spot on both tyres.

SteveCollett
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RE: 990 synro 1972 road top speed

Post by SteveCollett » Sat Nov 01, 2014 11:06 am

Before contemplating that drive I would also jack up the front wheels to check the bearings, and do a test drive to check the steering is good. Drove a Massey 590 that distance with a steering wobble which they were renowned for . Absolute nightmare!

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carpenter
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RE: 990 synro 1972 road top speed

Post by carpenter » Sun Nov 02, 2014 8:57 pm

i do 50 miles on road runs, but it know the tractor.
how did you get on?

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roscommon
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RE: 990 synro 1972 road top speed

Post by roscommon » Sun Nov 02, 2014 9:12 pm

Didnt do it yet my only real concern is the wobble in the rear back wheel, it could be the tyre as it looked a little soft, I will do the journey in sections 25 mile stop and so on , what's the mpg at top speed say 15 mph, ? Got some very good bicyclevlights for front and rear as nota . All lights work

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erkki
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RE: 990 synro 1972 road top speed

Post by erkki » Mon Nov 03, 2014 10:21 am

I have made over 100 mile days by my 1200 several times, even about 200 miles by a 990 on a sigle day. No problems ever. Not much flat spot on the rear tire is needed to make tractor wobble. Usually the flat spot is due to prolonged standstill on a hard yard and it will disappear soon on the road. 15 litres for 100 km is close to expected fuel consumption which is close to 17 mpg.

RGDS erkki

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RE: 990 synro 1972 road top speed

Post by Guest » Mon Nov 03, 2014 11:47 am

IOO km is 62.14 miles which would be, using 15 ltrs of fuel, 6.6 ltrs per km. Turning that into Imperial would be around 21 mpg. A 990 would probably travel a greater distance on the same amount of fuel but would depend on the terrain, engine speed and road speed of the tractor.

John_Allen
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RE: 990 synro 1972 road top speed

Post by John_Allen » Mon Nov 03, 2014 12:45 pm

I suspect the figures were estimated, so "cigarette packet" calculations will only be a rough guide - though I'd say that's about what my 995 does!

I'd like to say that I had a nice journey home with the 995 - but it wasn't really! Apart from missing a junction for a short cut, one of the cab doors wouldn't stay shut (and the other was blocked by the loader valves and excess pipe), the steering was a bit iffy and the brakes were nowhere near as good as they were when I test drove it without the loader! What seemed like a good idea wasn't all that clever - I might have had some severe problems driving a tractor at speed after it's long lay-up and was lucky to get home without incident (I did use some very quiet back roads to avoid most of the traffic).

The flat spotting isn't too bad until you've turned a corner or two and the wheels get out of sync - then you are a bit like the proverbial drunken sailor, swaying from side to side - it's a good work out for the beer belly though!

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ollek
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RE: 990 synro 1972 road top speed

Post by ollek » Mon Nov 03, 2014 1:59 pm

erkki said that the expected fuel consumption is 15 litres per 100 km and that this figure is closed to 17 mpg. Powerrabbit corrected this and said that the figure is 21 mpg. He also stated "using 15 ltrs of fuel, 6.6 ltrs per km". The consumption is not 6,6 l/km if the consumption is 15 l/100 km, it is 0,15 l/km (1,5 decilitre or 150 millilitre)). My calculations are shoving different figures. The figure I have got is 18,83 mph (this is in imperial gallons).

Guest

RE: 990 synro 1972 road top speed

Post by Guest » Mon Nov 03, 2014 3:21 pm

1 gallon = 3.78ltrs. 1 km = 1.61 miles. I'll leave it there.

To answer the original question, the maximum road speed of the tractor in HN3 (which is 12th on a 12 speed box)fitted on either 12.4/11-36, 13.6/12-36 or 16.6/14-30 rear tyres (of which all gives a rolling radius of 680mm or 28.6 inches), is 24.1 km/h or 15 mph at 2200engine rpm.

broadsword
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Post by broadsword » Mon Nov 03, 2014 4:21 pm

One `Imperial` ie UK gallon is 4.55 litres - One US gallon is 3.79 litres.

I`ll leave it there as well!!!

Cheers

Andy

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