What is normal?

[robelst]

Hello,
I picked up my TDM 850 yesterday. All seems fine, apart from the throttle response at low-ish revs. Sometimes it's fine, but nearly just as often it hesitates. No such problems art high revs.

Does this sound familiar? Could it be carb icing / moist in carbs / sticky choke / plug-lead, or is it a matter of "they all do that sir"? I've only ridden it in rather cold and wet weather. Also the bike had been stored since end of May, so maybe there's some gunk in tank or carbs

Also while playing this morning on the motorway I noticed that at 100 mph the engine is almost running at 7000 tpm. It seems happy enough doing this, but since it redlines at 8000 already I wonder if mine's running the standard gearing or not? My Africa Twin is similarly geared but that's a 60 bhp bike with a 110 mph top-speed and 8500 redline, so the TDM seems a bit revvy.

Otherwise it's great. So far it seems to fill all gaps that my Africa Twin has, like better comfort, better handlng / control, more poke. Well, apart from the throttle control that is.
I am also pleasantly surprised how well it runs at low revs in high gears and still revs up really-really fast, it's almost as flexible as a four but with twin-character. Very impressive

[alan]

I would check the chain adjustment should be between 40-50mm slack about half way along from the rear axle
Also get your carbs balanced got to be done every 4000miles approx.
dont know about the revs at 100mph dont travel that fast normally, i think 80mph comes in about 5500-6000revs not quite sure on that but others on this site will say so,should be a stamp on the rear sprocket that tells you No. of teeth on there.Then suss it from there

[robelst]

<!--quoteo(post=22069:date=Fri 17th Nov 2006, 12:15 PM:name=aytcat)-->QUOTE(aytcat @ Fri 17th Nov 2006, 12:15 PM) <{POST_SNAPBACK}><!--quotec-->I would check the chain adjustment should be between 40-50mm slack about half way along from the rear axle
Also get your carbs balanced got to be done every 4000miles approx.
dont know about the revs at 100mph dont travel that fast normally, i think 80mph comes in about 5500-6000revs not quite sure on that but others on this site will say so,should be a stamp on the rear sprocket that tells you No. of teeth on there.Then suss it from there<!--QuoteEnd--><!--QuoteEEnd-->
Thanks for that aytcat.
100 mph / 7000 rpm means 14 mph per 1000, so 5500 to 6000 means 77 to 84 mph which is kind of what you confirmed (not bad maths for a Friday afternoon is it?).
I am perfectly happy with that. I applied the cave-man approach of opening up the throttle trying to solve the response problem (of course it didn't), but usually I do up to around 85 and not overly interested in more

It just surprises me the TDM seems geared for a v-max of about 115 mph, that's why I wondered if all was standard on mine. As long as the engine handles it and fuel consumption low it doesn't really matter.

[iand1947]

<!--quoteo(post=22077:date=Fri 17th Nov 2006, 12:42 PM:name=robelst)-->QUOTE(robelst @ Fri 17th Nov 2006, 12:42 PM) <{POST_SNAPBACK}><!--quotec-->Thanks for that aytcat.
100 mph / 7000 rpm means 14 mph per 1000, so 5500 to 6000 means 77 to 84 mph which is kind of what you confirmed (not bad maths for a Friday afternoon is it?).
I am perfectly happy with that. I applied the cave-man approach of opening up the throttle trying to solve the response problem (of course it didn't), but usually I do up to around 85 and not overly interested in more

It just surprises me the TDM seems geared for a v-max of about 115 mph, that's why I wondered if all was standard on mine. As long as the engine handles it and fuel consumption low it doesn't really matter.<!--QuoteEnd--><!--QuoteEEnd-->
A brief review on the 850 I came across mentions doing 130mph/220 kph (indicated) at 8000 rpm. There's a proper mention somewhere - JBX pages? Basic gear ratios in Wikipedia (where else?)

[robelst]

<!--quoteo(post=22081:date=Fri 17th Nov 2006, 01:02 PM:name=Pict)-->QUOTE(Pict @ Fri 17th Nov 2006, 01:02 PM) <{POST_SNAPBACK}><!--quotec-->A brief review on the 850 I came across mentions doing 130mph/220 kph (indicated) at 8000 rpm. There's a ratio table somewhere - JBX pages?<!--QuoteEnd--><!--QuoteEEnd-->
That'd seem more likely than 115 mph indeed. Will see if I can find those stamps then

Anyway, I gave up being lazy and did some searches on the bad weather running and found some quotes / tips:
<i> -: I wrapped my coils and leads with self-amalgamating tape
-: a good idea is to protect the HT wire from moisture with a heat-shrink tube (glue inside is better).
-: Yes wrap tape around them, yes put a bit of silicone on. But most important, change your plugs for hotter running one's. Mine ran like crap until I did this and it runs luvverly now
-: my mk11 850 had a similar problem solved it by fitting a fenda extenda to front mudguard stoped water being sprayed on the engine
-: this is a pic of how i used self amalg. tape and silicone to waterproof them. (more pics available if need be) http://www.MyOnlineImages.com/Members/wi...CN0411.JPG
-: The only thing I can think of that goes half way to explaining that would be carb-icing.</i>

Lots about leads here. I had exactly the same problem on my Buell and simply bought a different pair of cables and new coil of a more decent quality (which is almost anything NOT bought from a Buell dealer ). I know this is not half as much fun of fixing the old ones, but has anyone ever upgraded these parts and if so, with what and did it help?

[iand1947]

<!--quoteo(post=22084:date=Fri 17th Nov 2006, 01:11 PM:name=robelst)-->QUOTE(robelst @ Fri 17th Nov 2006, 01:11 PM) <{POST_SNAPBACK}><!--quotec-->That'd seem more likely than 115 mph indeed. Will see if I can find those <!--coloro:#CC0000--><!--/coloro-->stamps <!--colorc-->
<!--/colorc-->then <!--QuoteEnd--><!--QuoteEEnd-->
Or just mark a tooth with a waterproof pen and start counting?

[steveglover]

<!--quoteo(post=22081:date=Fri 17th Nov 2006, 01:02 PM:name=Pict)-->QUOTE(Pict @ Fri 17th Nov 2006, 01:02 PM) <{POST_SNAPBACK}><!--quotec-->Basic gear ratios in Wikipedia (where else?)<!--QuoteEnd--><!--QuoteEEnd-->
The ratios on Wikipedia are for a 96-98 TDM with a final drive of 42/17.
99-02 TDM has a final drive of 43/16 (according to the Haynes Book of Lies).
100mph at 7000rpm seems a bit low geared, but I've never ridden an 850. The 900 pulls 88mph at 5000.

[iand1947]

<!--quoteo(post=22115:date=Fri 17th Nov 2006, 08:24 PM:name=SteveGlover)-->QUOTE(SteveGlover @ Fri 17th Nov 2006, 08:24 PM) <{POST_SNAPBACK}><!--quotec-->The ratios on Wikipedia are for a 96-98 TDM with a final drive of 42/17.
99-02 TDM has a final drive of 43/16 (according to the Haynes Book of Lies).
100mph at 7000rpm seems a bit low geared, but I've never ridden an 850. The 900 pulls <!--coloro:#009900--><!--/coloro-->88mph at 5000<!--colorc-->
<!--/colorc-->.<!--QuoteEnd--><!--QuoteEEnd-->
Are you sure? I'm sure mine's clocking lower revs than that - must check next time. Sorry about my boob on the 850 versions - I can never remember which Pharaoh ruled when

[ROB1]

My 96 model does 100 @6000 rpm on stock gearing.One tooth smaller front (16T) its rpm is 6400.sounds to me your bike is in 4th gear.just been out 105 mph = 7000 rpm in 4th gear.hope this helps.by the way it was cold so ive put myself out for this research.

This post was last modified: 19-11-2006, 02:19 PM by ROB1.

[wicklamulla]

<!--quoteo(post=22120:date=Fri 17th Nov 2006, 08:46 PM:name=ROB1)-->QUOTE(ROB1 @ Fri 17th Nov 2006, 08:46 PM) <{POST_SNAPBACK}><!--quotec-->My 96 model does 100 @6000 rpm on stock gearing.One tooth smaller front (16T) its rpm is 6400.sounds to me your bike is in 4th gear.<!--QuoteEnd--><!--QuoteEEnd-->


ya Rob has a pint here, those rev's/speed mentioned by Robelst sound odd

[steveglover]

<!--quoteo(post=22119:date=Fri 17th Nov 2006, 08:44 PM:name=Pict)-->QUOTE(Pict @ Fri 17th Nov 2006, 08:44 PM) <{POST_SNAPBACK}><!--quotec-->Are you sure? I'm sure mine's clocking lower revs than that - must check next time.<!--QuoteEnd--><!--QuoteEEnd-->
Pretty sure Pict, 88mph at 5000, 70 at 4000, both equate to about 17.5mph/1000revs.
I don't spend a lot of time at 88mph, its just a speed I pass through on the way to something more appropriate.......

[robelst]

I will look more closely tomorrow. I am sure it's in top gear, it's lively but doesn't feel overly revvy (and I am used to a Buell that does 125 mph at 5500 rpm ). I hope it's correct because I already love the engine as it is, it's just bl***y brilliant

[alan]

So everybody is out riding tomz then, checking there revs per mph lol

[alan]

<!--quoteo(post=22150:date=Fri 17th Nov 2006, 11:42 PM:name=aytcat)-->QUOTE(aytcat @ Fri 17th Nov 2006, 11:42 PM) <{POST_SNAPBACK}><!--quotec-->So everybody is out riding tomz then, checking there revs per mph lol<!--QuoteEnd--><!--QuoteEEnd-->
well i went for a ride seeing as it might be the last rays of sunshine for a while and can confirm my speedo/rev readings are 4000rpm =65mph
4250rpm= 70mph
if any ones is different to that sorry lol

[Jez]

Agree with Rob1. On my'96 100mph is 5700rpm indicated.

Strangely this is exactly the same as my ZZR1100, difference being the big Zed revved to 11,500.

[iand1947]

<!--quoteo(post=22145:date=Fri 17th Nov 2006, 10:21 PM:name=SteveGlover)-->QUOTE(SteveGlover @ Fri 17th Nov 2006, 10:21 PM) <{POST_SNAPBACK}><!--quotec-->Pretty sure Pict, 88mph at 5000, 70 at 4000, both equate to about 17.5mph/1000revs.
I don't spend a lot of time at 88mph, its just a speed I pass through on the way to something more appropriate....... <!--QuoteEnd--><!--QuoteEEnd-->
Sorry Steve - you were spot on: 5000rpm at 88mph for a 900 (I normally spend my time more at leisure).

Crossing topics, it gave me a chance to confirm that taking the beading off the edge of my MRA screen does seem to smooth the airflow and reduce noise, even on a blustery day like today. I prefer the look of the plain edge anyway.

[robelst]

So far, I've bought Haynes and it seems indeed the '99 and later TDM 850s have about 7.5% shorter secundary gearing (primary is same). I still have at least 500 rpm at 100 mph to account for, but there was a bathroom that needed tiling today, so still need looking further into this.

The bike looks bog standard, so I don't really expect non-standard gearing. But you never know of course. The only thing that looks a bit funny are the forklegs popping a few centimetres outside the top-fork clamp, but maybe that's standard too?

My only other complaint are the poor mirrors, I see a lot of my shoulders in there and they have little margin for adjustment. My well-trained god-like physique is partly to blame of course, but still room for improvement. Anyone tried alternatives?

[wicklamulla]

<!--quoteo(post=22217:date=Sat 18th Nov 2006, 10:12 PM:name=robelst)-->QUOTE(robelst @ Sat 18th Nov 2006, 10:12 PM) <{POST_SNAPBACK}><!--quotec-->So far, I've bought Haynes and it seems indeed the '99 and later TDM 850s have about 7.5% shorter secundary gearing (primary is same). I still have at least 500 rpm at 100 mph to account for, but there was a bathroom that needed tiling today, so still need looking further into this.

The bike looks bog standard, so I don't really expect non-standard gearing. But you never know of course. The only thing that looks a bit funny are the forklegs popping a few centimetres outside the top-fork clamp, but maybe that's standard too?

My only other complaint are the poor mirrors, I see a lot of my shoulders in there and they have little margin for adjustment. My well-trained god-like physique is partly to blame of course, but still room for improvement. Anyone tried alternatives?<!--QuoteEnd--><!--QuoteEEnd-->



Robel does that mean 1999 onward 850's have lower gearing and rev slightly higher in each gear or ???

your bike cud easily have non standard sprocket sizes, so it's worth checking.

someone has dropped the yokes down along the forks to quicken the steering slightly, i too did this.

you can get mirror extension nuts or some such thing to improve the rearward view, alternatively ya cud eat less pies

[robelst]

<!--quoteo(post=22218:date=Sat 18th Nov 2006, 10:48 PM:name=wicklamulla)-->QUOTE(wicklamulla @ Sat 18th Nov 2006, 10:48 PM) <{POST_SNAPBACK}><!--quotec-->Robel does that mean 1999 onward 850's have lower gearing and rev slightly higher in each gear or ???

your bike cud easily have non standard sprocket sizes, so it's worth checking.

someone has dropped the yokes down along the forks to quicken the steering slightly, i too did this.

you can get mirror extension nuts or some such thing to improve the rearward view, alternatively ya cud eat less pies <!--QuoteEnd--><!--QuoteEEnd-->
Hmm, rear sprocket turns out to be a 45 (instead of 43), so that's another 5% explained.

Will check the front as well, after I've finished my pies

[wicklamulla]

<!--quoteo(post=22261:date=Sun 19th Nov 2006, 12:55 PM:name=robelst)-->QUOTE(robelst @ Sun 19th Nov 2006, 12:55 PM) <{POST_SNAPBACK}><!--quotec-->Hmm, rear sprocket turns out to be a 45 (instead of 43), so that's another 5% explained.

Will check the front as well, after I've finished my pies <!--QuoteEnd--><!--QuoteEEnd-->

ahh oil bet she accelerates like feck though !