Taking it lower

[dobbi]

Hey all.

 

I am 5 foot 5 inches, perhaps 6 inches with a blow dry (165 to 168cm).

 

I bought my T7 3 years ago and it was stupid high for me but I had adjusted other adventure bikes to fit me right and I can now say I have got my T7 as perfect.

 

A lot of ignorant tall people say that, 'oh it is just your skill level, a bike when upright is in perfect balance, just be a better rider' and they are talking absolutle rot. Get them to ride a bike with a seat height of 1000mm and see how they get on.

 

It is not the seat height, it is the centre of gravity. With a shorter rider, it bring the centre of gravity  of the bike closer to your own centre of gravity then control when stood still becomes a massive wrestle. The lower the centre of gravity to the bike from your own the easier it is to control at low/ no speed.

 

So at first, the 880mm seat height meant I had to fully swivel off the seat to get one foot down. easy enough when the surface was predictable but a steep camber could be quite  a reach.

 

1) Lower seat and -20mm rally raid rear links.

 

This made things from unmanagealbe to just about getting by. Both feet on ground on tip toes but not a chance to get enough prurchase to reverse the bike.

 

2) -40mm Rally Raid rear links. drop front forks from 7mm fork showing at top to 12mm (10mm to 15mm if you include the fork cap)

 

Much better reach to the ground abiltly to revese bike in good conditions, better conrol of bike when stood still. Still feeling very top heavy hard to control bike through placement of body.

 

3) -35 Hyperpro progerssive springs on front, 85nm spring on back as im about 75kg net and can carry quite a bit of luggage.

 

Better reach to ground but now front end much too quick turning, not massivley fun to ride in lose terrain. soon went back to 7mm fork showing and thing became more relaxed.

 

However, after getting 3 sets of links, I could measure them and plot myself a graph

 

C to C is centre of each hole in the linkage to the centre and it appeared there was, for these measurements a fairly linear arrangement.

 

It appeared that about 16.7mm spacing between centre of holes would provide me with with 820mm seat height that I had so enjoyed on my previous adv bike.

 

So i bought myself some 6mm 25mm wide peices of stainless steel and armed with some very poor drill bits eventually got through thepretty tough stainless. The tops needed to be rounded off as they would catch the swing arm.

 

4) Home made (-60mm) linkage

 

balls of feet on ground both sides, easy to boss bike about from seated position. Confidence now where there was a lot of concern on the rougher stuff. This appears to be just right.

 

Now this is my own journey, so take from it what you will.

 

The big worry is that the back wheel is going to smash into the undertray and it has been constatly on my mind but I've hit a few hard rocks and done quite a few pressure on woops and there has been no contact. I think the 85nm spring has been a massive factor in not having problems so far.

 

I'm sure there will be some contact at some point but the ridabilty of the bike makes this risk absolutly worth while.

 

It is proper magic now!

 

 

Nice and low......

Edited October 29, 2023 by dobbi

[Rider 101]

Nice article.

I guess if you are really keen to find out if the rear wheel will hit the under tray you could remove the shock spring and see what the travel looks like.

[dobbi]

1 hour ago, Rider 101 said:

Nice article.

I guess if you are really keen to find out if the rear wheel will hit the under tray you could remove the shock spring and see what the travel looks like.

 

1 hour ago, Rider 101 said:

Nice article.

I guess if you are really keen to find out if the rear wheel will hit the under tray you could remove the shock spring and see what the travel looks like.

Oooh, now that is a good thought and would be definative.

 

However, I have no spring compressors (putting on the new one was a lesson in close call spring the chops) and I am half betting that the new 85KN spring is going some way to prevent contact.

 

We will see. Ive seen back wheels go through bottom trays before and it tends to be a bit cracky, melty rather than bang smash (however, context is everything) so lets see. I will report back!

[dobbi]

Perhaps to add to this,

 

The graph uses Yamaha stated ride height 880mm and then Rally Raid's -20 and then -40 ride height claims.

 

I cannot be totally sure of any, rear preload has stayed the same as stock, only being cranked upt to max when on a trip with luggage.

 

The graph showed a fairly linear relationship but I am sure physical limitations will soon see large changes in teh C to C value being of little help.

 

If you want to make a low-rider, it may not help!!!

 

Go easy!

[Just Footerin]

Thanks for posting this useful little graph. Just what I was looking for a few days ago.