Triumph Rat Motorcycle Forums banner

1 - 20 of 32 Posts

·
Registered
Joined
·
160 Posts
Discussion Starter #1
Hi all. Quick question from a Bonneville noob. First up I love the bike and buying one fulfills a dream I've had since I was a kid. It looks great, goes great and will sound great when I upgrade the pipes. My only criticism, and I wonder whether this is just down to the relative youth of the engine, is the slightly clunky power delivery in second gear. The bike is an 08 efi by the way with 1500miles on the clock.

Basically if I roll off the throttle and then back on in second there is a noticeable "clunk" as the power comes back in unless I slip the clutch a bit. It is very hard to smoothly apply the power. It isn't a big deal nor a big "clunk" but for example when going around a corner in the wet it would affect my confidence to power through it.

Simply is this normal? Down to efi? Tight engine? Anything else.

It doesn't affect my riding but as this Is the biggest bike i've owned I don't have the experience to know whether it is normal or whether I should get it checked out.

Thks
 

·
Registered
Joined
·
160 Posts
Discussion Starter #3
Hmm thks for that I'll take a look but I don't think that is it simply because it is really only noticeable in 2nd gear. I probably didn't describe it well as clunk is hardly a tech term. It is the transition from throttle off in 2nd gear to throttle on, no matter how gradually I apply the throttle there is always a slight jerk as the power comes in. I don't feel the jerk in other gears.

It could simply be the bigger engine that I'm not used to and a more binary power delivery but better safe than sorry.

Thks for the input
 

·
Registered
Joined
·
3,588 Posts
I have not ridden an EFI Bonnie, but the 1050 Tiger is VERY touchy on the throttle at lower speeds. I would not expect the Bonnie to be nearly as touchy because of the much lower torque and HP. Some things that might help: 1. At your next service, ask them to check the throttle cable adjustment--this has helped some on the 1050. 2. When you get new silencers, the dealer should load a new "tune" in the ECM and this may smooth out the throttle response at lower speeds. If you are hearing an audible clunk, then make sure the chain adjustment is correct.

Practice should help with smoothness, also--it helped me a lot on the 1050.
 

·
Registered
Joined
·
160 Posts
Discussion Starter #5
Thanks the lot for that. I think I'll go and have a chat with the mechanics at my dealer and ask them to check the throttle cable and chain. It does almost feel like there is a bit of slack in the chain that causes the jerk when throttling back on.

There is a small dead zone on the throttle when it is completely closed, i.e. i can move the grip back and forth half an inch or so without any impact on the throttle but I've had that on all my bikes so I'm guessing that is normal.
 

·
Registered
Joined
·
648 Posts
I agree with others here in that your throttle cable play and chain slack should be inspected. My '09 EFI Bonneville T100 is the smoothest running and shifting new motorcycle I've ever owned. It now has just under 500 miles and shifts as smoothly as my Hondas with 35,000 miles. Every bike I've owned prior to this Bonnie has had a tight transmission for at least the first couple thousand miles but this bike is the exception. EFI throttle response is perfect, both before and after remap with Togas. At 500 miles, this bike has been wonderful so far! :D
 

·
Registered
Joined
·
648 Posts
There is a small dead zone on the throttle when it is completely closed, i.e. i can move the grip back and forth half an inch or so without any impact on the throttle but I've had that on all my bikes so I'm guessing that is normal.
1/2" is not normal. It should be more like 1/4". At least that's how I adjust mine.
 

·
Registered
Joined
·
10,215 Posts
Slack in throttle cable

Should there be any slack in the throttle? I adjusted most of the slack out of mine, only have a millimeter or two of play in it, enough so I know that it's not over-tightened.

I don't know if that's the right thing to do, but I can't imagine any reason not to adjust it that way.
 

·
Registered
Joined
·
160 Posts
Discussion Starter #9
I was exagerating on the throttle play. It's only a 1/4 inch or so though I agree better not to have any unless it's there by design for heat expansion tolerance.

I should stress my issue is not in changing gear which is dead smooth but when I excelerate after closing the throttle in second. It just feels like there is a bit if slack so when drive engages it is with a bit of a jerk unless I am exceptionally smooth on the gas. It just reduces my confidence a bit in slow corners when you tend to be low revs in second. I'm sometimes tempted to shortshift to third because the power comes in more smoothly.
 

·
Registered
Joined
·
648 Posts
When you rotate the throttle all the way off and forward you should feel a very small amount of free play before it begins pulling on the throttle. If you do not, it's too tight. The idea is to eliminate as much slack as possible without putting too much tension on the cables from over tightening them.
 

·
Registered
Joined
·
445 Posts
Mine Smoothed Out

Hi all. Quick question from a Bonneville noob. First up I love the bike and buying one fulfills a dream I've had since I was a kid. It looks great, goes great and will sound great when I upgrade the pipes. My only criticism, and I wonder whether this is just down to the relative youth of the engine, is the slightly clunky power delivery in second gear. The bike is an 08 efi by the way with 1500miles on the clock.

Basically if I roll off the throttle and then back on in second there is a noticeable "clunk" as the power comes back in unless I slip the clutch a bit. It is very hard to smoothly apply the power. It isn't a big deal nor a big "clunk" but for example when going around a corner in the wet it would affect my confidence to power through it.

Simply is this normal? Down to efi? Tight engine? Anything else.

It doesn't affect my riding but as this Is the biggest bike i've owned I don't have the experience to know whether it is normal or whether I should get it checked out.

Thks
I've got 1300 miles on my Spoked EFI Black and this eased up considerably as she was broken in. I also my decel popping through the break in period. I kinda miss it.

As for throttle play, the manual that came with the bike shows 2-3 mm of play.
 

·
Registered
Joined
·
209 Posts
Throttle cable slack is important on all bikes. Its there to prevent the throttle from self actuating when you turn the handlebars full lock.
You'll know if there isn't enough slack - turn the bars full lock both ways with the engine warm and ticking over (don't touch the throttle), if the cable outer is too long (no slack) the engine speed will pick up.

The amount of slack varies from model to model but typically 2-4 mm in my experience.
 

·
Registered
Joined
·
160 Posts
Discussion Starter #13
It sounds like the slack in the throttle is fine and maybe the jerk once drive engages will loosen up as I put on the miles but I'll probably get it checked over anyway. I'm not confident about adjusting the chain myself just yet. Thanks for all the feedback and advice.
 

·
Registered
Joined
·
267 Posts
The throttle cable doesn't sound like the problem if it only happens in 2nd gear. I'd try a few experiments to see what happens if...

you leave it in 2nd and roll on and off the gas, try it a few times with more abrupt throttle moves

or it only happens when you shift from 1st to 2nd

or it happens in any gear when the throttle change is extreme
 

·
Registered
Joined
·
1,498 Posts
I had a Sprint ST955i which suffered the same problem and I always felt uncomfortable going around round abouts.The throttle was like a on/off switch. The solution I found was to ride the rear brake which smoothed out the jerkyness.
;)
 

·
Registered
Joined
·
160 Posts
Discussion Starter #16
The throttle cable doesn't sound like the problem if it only happens in 2nd gear. I'd try a few experiments to see what happens if...

you leave it in 2nd and roll on and off the gas, try it a few times with more abrupt throttle moves

or it only happens when you shift from 1st to 2nd

or it happens in any gear when the throttle change is extreme
It is only really noticeable in 2nd gear and possibly having just changed up from 1st. I only really notice when on roundabouts when I flip up to second and then would just be low and steady throttle around in that gear but as the poster above says the power comes in like an on and off switch even with very gentle throttle manipulation. It is very hard without back breaking or slipping the clutch to maintain low throttle in second because you are jerking forward or back on/off which on a wet roundabout is a bit scary. On a straight you don't even notice.

Maybe we just have more rain and roundabout in this country :)
 

·
Registered
Joined
·
818 Posts
Try shifting from 1st to second without using the clutch,your probably pulling the clutch lever too much,I had the same prob with my 08 bonnie-the new bonnies gearbox and clutch is very slick,does't need a lot of clutch to change gears although on mine from 4th to 5th always needs a full pull on the lever to kick it to 5:)J.B.
 

·
Registered
Joined
·
1,886 Posts
I had exactly this problem with my new 09 Thrux. Throttle on and off like a switch in second. It kicks in with a jerk at low speeds, and turns off on throttle shutdown immediately. Having been used to reducing but residual power on a carb bonnie, it was unpleasant. It is nothing to do with the gearbox or cable - (I think) - it is EFI! I dicussed it with the dealer. The solution or part solution is:

1. Be aware and alert that this is going to happen - stating the obvious but if you have not ridden for a couple of weeks, you forget
2. Maintain the revs slightly but as one poster says, fettle the clutch to retain control
3. Use the back brake to give control whilst retaining some power.
In other words, avoid throttle shutdown.

I find because of the issue, it is not great for town riding, but a blast on bypasses, A roads etc where traffic lights are at a minimum.

But then, that is why I drive a fully auto Vespa 125 in town - more responsive, easier to control easier to stop!
 

·
Registered
Joined
·
160 Posts
Discussion Starter #19
Thanks again for all the input. I'm glad I'm not imagining it. It really doesn't bother me too much and practise makes perfect when riding. I'm going to take a ride on a friend's 2006 Carb model and compare the two.

If it is the EFI maybe it can be improved by a new map otherwise I suppose I could change 2nd gear to a slighted higher ratio which might smooth things out a bit.

Given that I live in central London and ride to work every day it isn't exactly holding me back.
 
1 - 20 of 32 Posts
Top